Depression, Self Loathing, Self Injury?

I know, its a cheery topic. For the last year, I have been struggling with depression. But here is what is odd, and what I wonder if anyone else can help me make sense of: I feel more depressed while and directly after I am around family, friends, or peers. By the time we part, I feel like crying. I have burned myself a few times and am afraid of creating a permanent habit. It doesn't seem to matter who I am around, it always makes me feel un-empowered, ugly, and overlooked. It always seems like people expect me to be a certain way or they withdraw all respect or kindness. It's like my life is theirs rather than mine. But the only time they notice me is when I take a step towards the edge of the box they have built for me. And in comparison to them, I am worthless- I have a bad personality, I am not attractive, and I have nothing to offer. The worst part of it is, I am a Christian. I am struggling, but I truly want my life to belong to Christ.