I don't know what's happening.

I don't know why I'm feeling like this. Have been just detaching myself from everything and everyone around. I don't talk a lot, so the only way I express myself is by crying in the bathroom. I just feel nobody likes me. I don't feel good emotionally or physically. I feel I have disappointed everyone in my life. Never made anyone proud, no matter how hard I try. I feel scared to trust people, I feel they will always go away from me. I feel vulnerable. I don't feel like going out, or talking to anyone or doing anything. And the worst part is I don't know the reason I feel like this.