Broken

I recently cut ties with someone I've been in a relationship with for six years. He kept promising marriage but always had one thing after another that he felt I needed to fix. This became mentally draining and I decided to end things. No more than two weeks later I caught him with someone else. That it itself seems to be more than what meets the eye and I really believe this has been going on the whole time. I'm praying and asking for God's strength but sometimes I find myself drifting and thinking negative thoughts. Hoping I can heal from this and be able to love and trust again!!!