Me and my ex broke up

Me and my ex broke up. I broke it up after Christmas. I thought I was in the reality I was falling out of love with her. I really wasn’t. I was just trying to hide my emotions and the way I felt about her. We had a gorgeous son, I destroyed her because I cheated on her and didn’t own up to my mistakes but now I really realise I destroyed her amazing heart that shouldn’t of been destroyed in the first place. Now I know that feeling of her talking to someone else and that actually breaks my heart. I know the feeling now. I’m so sorry for what I caused. It was my own actions. Anyone have any advice or help that will guide me into the right direction?