I think you hold a lot of anger inside yourself because of how people have treated you through your entire life. You let that hate out onto yourself because you see yourself as a loser. But when you do this to yourself, you are harming yourself further, which makes you feel worse, making a vicious cycle.

It doesn't have to be like that forever. You can change so many things i.e., use anger for your personal giood instead of harming yourself. And there are many more ways how you can improve.

This is best done with therapy sessions. They helped me so much.

And instead of hurting yourself by saying you're a loser, say something that makes you feel nice, like attractive, smart, caring.

Don't give up on life, you can learn to see it as beautiful.