How do I change to be a better person for myself and the people around me?

Hey. I am a 20M, and I got dumped by my girlfriend because my depression got out of hand. She said that I needed to focus on myself before I need to love myself. I am asking, how do I love myself?

I ask this because I want to be a better person, and the pain I've caused other people really bothers me. A lot of my closest friends have told me that "everyone hates you." They don't say why, but I'm 99.9% sure why. I have a battle with lust, and I've been on the losing end for half of my life. I've been lustful toward my women friends and lost them, and I have been angry because I haven't gotten my way with some friends. That's the pain that they are talking about.

I also tend to beat myself up over things, and as a result of my being lustful for women, I don't really have friends. I can talk to people and everything, but people don't hold conversations with me unless they're my friends from grade school. Everyone else tends to go off in their own direction. I don't know how to stop pleasuring myself with other women; I just want to live their lives. I am sick and tired of being this kid. I want to change, but I can't. can't take that extra step to change. I always come back to this BS.

However, I am finally getting on antidepressants soon, and I just wanted to know what some things you did that helped you try to love yourself?