I don't think I'm going to talk my now ex boyfriend about being bi
Why don't you want to talk to him about being bi?
When I told him I have a different sexuality, he became violent, so I left.
When a relationship ends you don't have to talk to them if you don't want, especially about things that lead to violent fights. It is safer to stay away from them.
That sounds good. I can focus on myself and find someone that truly understands me more than him.
Now that's the spirit you should have regarding exes! You really need to move on because going back would only cause more problems regarding your safety and sexuality. I hope you will be able to find someone who can protect you.