Why am I the way I am? (My real life story)

To whom it may concern: There's a reason why I'm the way I am. Always depressed, sad and what not. It's a bit of a long story really. See when I was young, around four or five, my mother decided that she wanted to leave me with my grandma and move to someplace else and not come back for several years. I eventually was adopted by my aunt and uncle, but the post traumatic stress I had from her leaving left me with a lot of bad qualities. I got into fights a lot, especially when someone talked shit about her. They were right by the things they said, but I was still not ok with it because they knew nothing about her and only I could say stuff about her. So I didn't have really any friends and honestly, I didn't want any. Because of her leaving I also had a hard time trusting people and crippling depression and anxiety. I still do, but it's not quite as bad as it had been in the past. But because of all this, I didn't make any friends for along time until I was in middle school. My first and bestest true friend decided to sit next to me at lunch one day and he asked me about my past and why I acted like I do. I told him, and he listened and helped me get through it. Granted, I still get down a lot, but now that I have him as a friend along with others I met along the way, I don't have to be alone in my depression. I still worry about losing my friends, but they're always there to prove me wrong in that. So if I act sad and depressed, don't think I'm being dramatic. Instead, understand that I'm going through a rough patch of remembering my past. I usually hate talking about my past, because it brings back so many bad memories and my depression and anxiety. But you need to know why I hardly ever smile. Why I don't socialize much. And I will try to change it, but most days it will be very hard. So bear with me. Thanks for listening. -spartan