I totally sympathize. It seems that when I do find another mom to hang out with, we just don't click together. I've kind of had to feel it out. I have one mom in my neighborhood that I can usually drop in on, except on Mondays and Tuesdays, and our kids can play. Some days we strike up a conversation and others, the kids are in our face and we can't think of much to say to each other. It seems so many other moms are too busy, they work, have too many kids, or even have animals, so while I'm welcome to come visit they are always on the go. My husband and I look forward to having a house where we can invite people over for Sunday evenings, get a little group together and enjoy each other. He also talks with friends on forums online, and they plan to get together for long drives & such (it's a car forum), so I look forward to someday being able to afford these vacations. Meanwhile I go to the grocery store, I sometimes attend MOPS (I don't love the spiritual 'message' even though I am Christian, but I often go anyways because it's a chance for my kids to go play with other children and I do get some conversation). I wouldn't say that cures me of my loneliness. Some of us are so blessed to be so different from each other, I guess it's just one of those things.
I am also not close with my mother, she never calls and my MIL, well I could tell stories, can't we all? In any case, I get a kick out of answering questions on here, reading articles and doing anything to pass the time and make me forget that I'm alone.
I guess my point is you are not alone in this feeling of loneliness. But things pass and this should get better for you. Take some classes and do what you can, then just wait for the sun to shine on the things that are beyond your grasp. Last of all, if you are religious, and I hope you are, pray for friends, and someone to be there for you.