Such a shame that their parents are spending hundreds of thousands on their high school education, just for them to grow up with such a lack of sophistication and an inability to think with nuance.
OP, you made a fantastic decision!
@“Snowball City” , agree 100%!!! We had the same comments directed towards us because we chose to even consider an ‘out of the box’ college. However, after visiting, speaking to lots of students & faculty, DS is comfortable with his decision and I feel that it truly will be his home away from home for the next 4 years. We joked that he chose this college because their colors matched his complexion- that will be our standard response to the ‘experts’ who feel that they need to weigh in on our decision. You chose a school that suited you, where you felt comfortable and a place that would help you to become the best you over the next 4 years. Whatever you saw in this school resonated with you and you don’t have to justify it to anybody. Pick a humorous, firm response to the experts and hold your head high. Well done on your options and on your decision!
It’s really splitting hairs to talk about quality differences among schools of that caliber. They’re all good, but the one you picked has a key difference: it’s affordable and won’t leave you drowning in debt.
People just feel threatened and judged when someone else hasn’t signed on to their values. “Wait, what, there are people who didn’t drink the Ivy Kool-Aid??!!”
“You will get to devour some 2500-3000 meals there. Bon appétit!”
Literally! 
Consider also that you go to a Northeast boarding school. Some kids literally do not consider money (believe me, I can relate since I’m also going to an expensive private school). I also know someone who turned down ivies for merit at WashU, and I respect them so much for it. WashU is an amazing school, and the people I know who are going there seem to be really happy about it.
It’s like going to a really expensive sushi restaurant over a cheaper one. That california roll could be good af, but it sure as heck isn’t worth paying $20 for.
Similar situation but from a teacher. My DD excels academically and was admitted to all of the colleges she applied to. She decided to go to UNCSA (school of the arts) instead of going to UNC chapel hill or Wake Forest U, etc… her AP Biology teacher can’t understand why she would pursue technical theatre and not a STEM career.
Like everyone else, I’ll congratulate you on your accomplishments AND making the smart choice for you and your family. I’m a big believer in your education being entirely what you make of it; school fit is helpful, of course, and as others have said, it’s hardly like you’re turning down Ivies to go to a community college, but you will clearly succeed wherever you go!
That said, my daughter turned down a “better” school to go to the school that gave her merit money (and felt like a better fit), and her Ivy-bound “friends” in high school behaved similarly. It sure did make it easy for her to leave and go find new friends, I can tell you that.
People might be saying that because that is how they would choose. But they are not you!! You are choosing an excellent school where an excellent student can get an excellent education. You will not be an anomaly there either. (And you will be better positioned financially for grad school, or simply to take a job you like rather than because it’ll pay the debts, in 4 years.) Don’t look back!
Speaking of excellent, pick up a copy of the book "Excellent Sheep ". I suspect much of it will be familiar to you. It is always hard for “sheep” to pass on an opportunity that is highly selective simply because it is so selective.
Note that at this one very small part of your life, everyone thinks they have input into where you “should” go.
After this, you will just hear people say “Great School!”
Those people were not there when you visited the schools and saw how it “fit”.
Those (teenager) people probably don’t know how highly esteemed Wash U is…they are just going with “what they have heard about”. They may think Wash U is a state school in Washington State.
Those people don’t know that Wash U gives merit scholarships while the Ivies do not.
They don’t know that you have to be very high academically to get $30K scholarships at Wash U.
They are not paying for your college. “Sure I would love to go to an Ivy…can you give me the extra $120K I am not paying? No?”
They don’t know how employers would love to hire people from Wash U or ivies.
Although these are your peers, they are just teenagers.
Thank you all so much for your incredibly kind words! I’m blown away by this reassurance, and it truly means a lot to me.
Congratulations on your achievements! I also faced a similar decision - I got accepted to UC Berkeley, among others, but couldn’t attend because of financial reasons. I’m going to UC Davis, where I got a $30,000 merit scholarship, next year, and I’m ecstatic 
No matter what, people will have their opinions, but you do you! If you worked hard enough to earn admission to all those schools, I’m sure you’ll be successful and happy regardless of the school you attend. And W&L is fantastic anyway! Best of luck next year.