Sounds like you had a nice evening last night! First day jitters, not unusual!
Maybe that was the last minute decision for her to come - she wasn’t going to come because she needs to study for boards, but when she realized there would be a chunk of time your S would be gone she figured that she could study then.
So, she has been outside on our balcony studying for over two hours. She has not eaten a thing and has not even had water!!
I’ve offered twice. Now holed up in our bedroom so she doesn’t feel like I’m watching her study. And she can now get water without having to walk past me. But she hasn’t!
She never came in or got water or had anything to eat or drink until ds and dh got back at 1:30.
Last night she realized she has a travel nurse friend doing a stint about 40 minutes away from us. And invited her to come to the beach today. She arrived around 1:45 when ds, gf, and dh were eating their lunch. Offered friend sustenance. Declined. Friend much more chatty with me than the gf. The three of them are now down on the beach. Guess I’m inviting friend to stay and eat dinner with us??
She does not seem all that interested in getting to know us 
. Dh is annoyed (rare) but going with painfully shy.
She is awkward at best. I’m wondering if she struggles with anxiety. To our knowledge ds has not had a gf before. We don’t know his type, but we are both kind of baffled
I know - in hindsight, I wonder why future DH did not offer to sleep on the sofa or something (us being together was definitely not an option with MIL). They didn’t have a ton of room, but I am sure something could have been arranged.
Fortunately, for the rest of the summers that I visited, one or both of his siblings were living and working at the beach so there was almost always a room and bed for me 
Sorry to sidetrack @Hoggirl but thanks for keeping us updated on the weekend. Try not to come to any conclusions yet
I would give it time. I would infer that her being shy/quiet is her being nervous because she cares about the impression she makes (rather than the opposite).
Thank you for the update, @Hoggirl .
So did gf’s friend stay for dinner?
When does gf and S leave?
Did your H get any info from S during their fishing time?
Can I say this without getting in trouble?
My quick take–she wanted a beach vacation. Be pleasant and tell (nah, don’t say anything) son to keep looking…
Any girlfriend that invites her girlfriend over to her boyfriends parents house–is not the one.
That’s a bit more than just rude. That’s a volume of unspoken conversation.
But I’m sure your son doesn’t need to be told. Just smile and nod. No negativity. The right one is still out there. But (because I’m me and nosy/worried/always have an unwanted but hopefully loving opinon) would probably ask him after she’s gone how he feels about her and how he thought the weekend went.
Maybe the gf asked the OP about inviting her friend? It sounds like the gf is just not the parents cup of tea. That happens and is always tough. My younger son had a girlfriend of 2 years that I was not all that wild about but I did not tell my son that. They broke up and I was not that upset, but my son was initially and I felt so badly for him.
I just wish he’d find another girlfriend! I just want him to be happy and he’s a great catch!
I wouldn’t judge too much on a first visit. I would hope the gf asked, at least the son but hopefully the parents, if the friend could come to the beach. Or maybe the friend invited herself? I certainly wouldn’t decide she is not the one for the son based on this!
Kids sometimes look at beach houses as a vacation place where the parents happen to be rather than a “meet the parents” weekend. Not an excuse to be rude of course, but she may not have thought that it would be a big deal!
I don’t necessarily think it’s weird that she invited a friend to the beach, depending on the circumstances. Did the OP’s son and GF already have plans to go to the beach today? Like, did they already have plans today that did not involve the OP and her husband? Because if they had already been planning to spend the day without the parents, inviting her local friend to join them shouldn’t be an issue (though staying for dinner is different…).
My D and her fiance live across the country. We’ve actually only met him on two occasions and both times, numerous people were around (first time was at D’s college graduation, and second time was last Christmas when he came for 2.5 days, when my SIL was also visiting from the west coast, and we were spending the two days he was here with my extended family). Anyway, if they were coming at a different time of year, and planned to hang out for the day together without us, and he had a local friend he was interested in seeing, it would not bother me one bit. However, I know my daughter would probably mention it to me first, especially if there was any expectation or desire for that friend to be entertained/fed by us as well.
Without knowing more details, hard for me to judge whether it’s rude for the GF to spend time with her friend. Maybe she mentioned possibly seeing her friend to the OP’s son and he told her it was fine w/o checking with his parents first? Maybe she then assumed it would be ok?
It’s easy and understandable to immediately blame the significant other. But perhaps this is all just a simple misunderstanding between the OP & her DS & his GF. For example:
OP’s possible point of view/expectations:
DS’s possible point of view/expectations:
GF’s possible point of view/expectations:
When my kids SO’s stay over, I know they are here to see my kids, not me. My 21 year olds boyfriend of 3+ years has stayed her many times, once when she was out of state (he drove her to Boston and stayed here on his way home to Long island). He has friends who go to college 5 miles from us and live in our town, so they get together almost every time he’s here. Since we have 5 kids, our home always has folks coming and going, all are welcome (I miss the chaos).
Hard to jump to any assumptions because we (and apparently the OP) aren’t sure of the thoughts of the kids.
I think it’s ok that the girl invited a friend over, she lives a plane ride away and wanted to see a friend.
Besides the “couple” are soon going to be living across the country from each other. Hard to know what the future holds.
Doesn’t really matter the OP is giving her some slack, and that what’s count. That her son knows his parents are a safe place to bring a friend of any gender.
When my kids visit from out of town, I love seeing their local friends. I know my sons will want to go out and see others when they do visit. I actually think it’s probably a good sign that the gf wants to see her friend. She has connections with friends, not a bad thing .
Hope you feel the visit went well @Hoggirl !
They are leaving together. Different flights b/c going to different places, but around the same time. There will be no alone time with ds
Okay - update and some clarifications.
Things improved last night. GF’s friend left the beach - did not even have the opportunity to invite her to dinner - she had other plans, etc.
I do not recall if GF specifically asked if her friend could come to the beach. I was very clear with ds via texting before their arrival that we were going out to dinner on Friday night, that dinner was in on Saturday night, and Sunday night was TBD. However, I also told him that we wanted to hang out with them, but they were also free to go and have some time off to themselves. Offered my car, etc.
When they came back from the beach, ds said, “Friend said thank you for your hospitality.” I mean I didn’t do anything for the friend - I just happen to live at the beach. We did have to assist with parking. GF also said, “Thank you so much for letting me have my friend come over.” She also asked if she could help with dinner and complimented what I fixed for dinner.
I think she struggles with some social anxiety. She told a story of meeting a large number of ds’s friends all at once at one of said friend’s birthday parties. Talked about how nervous she was, knocked over a drink on one of the girl’s pair of expensive ($600!) shoes, etc. Talked about how protective friends are of ds and how she was being asked a lot of questions. This young woman comes from a very different socioeconomic background from us and from most of ds’s friends. His friends (I have met about half that were at this birthday party) are wicked smart, polished, business professionals. Tons of extroverts. Tons of MBB consultants and bankers and tech types. I think they are all great, but they are intense folks. Anyway, by listening to her talk about that, I think she is just not super comfortable/confident in social situations where she does not know people. None of them are medical types, so not much common ground or ability to appreciate where her smartness lies.
Now, when she starts talking about her work, her career goals, her upcoming DNP (which she is having paid for with a highly specialized fellowship), it’s like she is a different person. She is VERY confident professionally. I just don’t think she is confident socially.
This is not a beach place but our home. Interestingly, the friend asked that. She - it was obvious - comes from money. “Do you own this or rent this?” Me: “Oh, we own it.” Friend: “You don’t live here full time do you?” Lolol. I guess because it isn’t super large. Quite the contrast to the GF.
After dinner we watched sunset and talked quite a bit and all played cards. It was fun.
Honestly, if the girl would have just at least taken some water yesterday morning, I would have felt a lot better! I don’t think she has had anything to eat or drink since she got up today either??
They are both studying now. My ds has a pre-MBA global experience trip coming up in a couple of weeks and has an assignment for that. She is studying for her boards. We are all going to a brewery and to listen to live music there later on today.
Honestly, if my ds were a better communicator with me, it would have been better. Send a text: “Listen, Mom - GF is not much of a morning person. Don’t worry about feeding her breakfast or anything. She rarely eats in the morning. She’s also pretty introverted until you get to know her, so don’t expect her to chat it up with you while I’m fishing with Dad. She needs to study, too.” Which she had said that last part the first night they were here - that she needed to study while the boys were fishing. But, his giving more intel would have been a kindness to her, IMO.
They both leave very early in the morning, so no alone time with ds this visit. We will see him in a month when we help him relocate to his MBA program.
Edit: And dh had no time to chat with ds (not that they would 
, but that’s a different thread) on the fishing trip because one of my dh’s friends went with them and even drove them to the boat place - so no alone time with ds and dh either
Too bad about no time with Ds for you. She sounds shy and not good at engaging with people that may intimdate her. Give her a few years in health care and those skills will develop.
I would have no problem with any guest touching base with a local friend and inviting them over. Though I know the beach house aspect can be burdensome due to number of uninvited guests at times. Sounds like a relief that the friend was more chatty and engaged.
I was only around friend around 15-20 minutes. We weren’t down on the beach with them.
But, the contrast was definitely stark in terms of conversational skills.
Okay, that crowd sounds pretty intimidating, I have to say. I don’t think I know anyone who wears 600 dollar shoes, poor girl.
I don’t think being uncomfortable with a different (presumably much higher) socioeconomic group means someone doesn’t have good conversational skills. Just perhaps not ones suited to that particular situation.