Like Settie, I don't have any advice, but sometimes it's nice knowing you're not the only one. As I posted in another thread, I started to feel this way around 10th grade/sophomore year of high school. I started to do online school and everyone who I thought were my friends (one being a friend since the age of 5), just stopped contact with me, even though I'd try really hard to stay friends. I'd tell them how I felt like I was unwanted and nothing changed. Me and the friend I had since 5 still stayed friends and saw each other every now and then.. until she got a boyfriend. She brought him over to my house to hang out so I decided to add him on msn and we became friends pretty fast which my friend didn't like. She was so jealous of our friendship that she told him very awful things about me - things that weren't even true. So I get how it is to have (who you thought were) good friends just turn on you like that.
Now I just don't care about finding or having friends, because what's even the point? I get that many people are happy with having a bunch of friends and I can understand that, but it's just not something I desire or enjoy. I don't care to open up to anyone, because again, what's even the point? I have one person who I truly care about and who cares about me, which is all I want/need.