How can I stop comparing myself to others when..

I've always been at the sidelines because someone else had this physical trait.. 

I've been treated..the way i know I didn't deserve because I don't know..

Probably not to pretty enough to be cherished and be proud of? I don't dance or sing or rap or talk well or whatever.

Probably not that significant to receive just one praise ?

All the treatment from others..all that pain is locked up inside me. I can't seem to let it go. What should I do..It's just so hard to be happy, it's so hard to trust and it's so hard to forgive. 

I just hate it when people tell you that you have to/you can do it. They just don't understand how much it hurts. But yeah you have to, but you can't , it hurts so much.