How do I resolve this situation with my friend?

I guess I put too much emotionally into one of my friends, because I had never had really any friends that were girls. So I would talk to her about everything, but I never wanted to burden her and maybe it got to be too much to her, because I find out that she didn't want to talk to me anymore, even though she said she was there when i needed to talk. And I had been trying to give her some space a few days before and she was someone who helped me with my depression, but now after her and another friend saying they are tired of my complaining, I'm relapsing back even worse to where I was before. I am trying to resolve the situation with the other friend, but I've tried to figure out what the deal is with her, and she doesn't want to respod. I have no problem giving her space, but I really don't want to lose her as a friend, as its hard for me to meet people; and she actually seemed to pay attention. And Ive had similar things happen in the past where a girl I talk to just loses interest and it makes me feel like I'm incompatible with women. All ofmy friends have some sort of lady friend except me and it juat makes me feel incredibly lonely. And if it helps, I just turned 21last month, but I've always hung out with my older brother and his friends for most of my life, so I feel a little bit older than the friends that are my age.

So what do I do, and how do I work this out?