How do I move on

I have been with my ex bf since 2018. We had a really inconsistent on and off relationship. He cheated on me twice. I guess the first time I returned was because I really thought he had changed. He then went on to marry someone else. My heart was really broken. His marriage did not last long and he got divorced. During the divorce proceedings he came back to me asking for forgiveness. I said no even though I loved him. In one week time I saw him with someone else. I mean it really broke my heart how people use you for their benefit