Why am I like this?

As a kid I had satisfaction in seeing others cry as I used to get bullied myself and always used for money that made me hate people. Girls in school wouldn’t sit next to me cuz my acne was bad .

I used to get made fun of from teachers,students and even my own parents so when I finally found love with a girl I became overprotective to the point I became controlling all that caused me to eventually lose her although she came back and I changed for her but so did she and eventually left me again and hasn’t come back since . All this has given me suicidal thoughts what do I do