Hopefully things have gotten better for you, OP. I tend to think of a study abroad experience shaped kind of like a parabola - the beginning is amazing, the middle can sometimes be a struggle as you settle in and miss home (and adjust to a new language and cultural practices), and once you get settled things even out and get amazing again.
One thing I noted, though, is that you Skype home almost every day. That sounds a bit excessive, and ironically talking to your parents and friends so much is keeping you tethered to the U.S. and not to the program. Try cutting down your home communication to 2-3 times a week for an hour or two. Put that time and energy into doing things in France.
Secondly, as others mentioned, university/young adult culture is very different in Europe. There aren’t organized youth groups or college orgs and campuses to bring young people together somewhat artificially, and most of them tend to meet each other doing other things. You can’t rely on others (visiting your friend, hanging out with the other Americans in a different program) to make life feel good for you - you’ve got to go grab the opportunities yourself.
One really, really valuable thing I learned in my study abroad program is the value of solitude and how to be comfortable being alone. I actually was in one of those American programs with regular travel and excursions, but there was also a lot of free time, and my American classmates were close but also independent. I spent a lot of time exploring Amsterdam by myself and traveling by train to other places. At first it was hard and I felt lonely, but the more time I spent getting comfortable with myself and with being alone the better I felt. Soon it became a really joyful experience to discover something on my own and sit quietly sipping coffee in a Dutch cafe reading a book or riding my bike through shortcuts I’d found. Honestly, I think that self-discovery and comfort with being alone was probably one of the more important things I brought into adulthood. So maybe also spend some getting to know yourself and exploring on your own, and trying to enjoy being alone? Traveling alone can be really awesome; you dictate your schedule, what you do, where you go and what time you do it.