C.G.
Wow I have the same problem, however I'm not even from this country and didn't speak English well when I got here 10 years ago, I thought that was why I couldn't make new friendships. I have only made one lasting friendship that I met two months after I got here; I used to invite my next door neighbor's children for playdates with my daughter and they never accepted. I was never impolite, or rude. they just weren't interested. I use to cry so much about it until I got use to the loneliness. This might be really wrong of me but I just thought this was the American way to do things, I've noticed everyone here is very reserved even between family members (please don't be offended, I know not everyone is like this, it's just something I noticed over the years).
I spent two months in New york one time and never felt like this; I'm in the same boat in the sense that my husband has such a great job here that we cannot simply leave and find another one as good as this one that easy.
However one thing I really like is that when I sit at the mall's playground or park etc. I talk to the other moms and and they're really friendly. It's close friendships that I haven't been able to make but I usually converse with people at the mall, kid's lessons etc. That social contact is enough for me, but years ago I craved more.
I wish you good luck and remember there are tons things to do that you can do alone too. I love reading at the library, going to the farmer's market or even shopping by myself.