Love lost

Hello, I'm just writing this for myself. If anyone sees it you are welcome to comment but just be gentle please. I'm 57 (F) and in January it will be 4 years since I separated from my ex husband. We were together 24 years and as all couples we had good and bad moments. I was very much in love with him (still am) But he became distant and I felt like something wasn't right. I started the divorce thinking maybe he would fight for us. He didn't in fact about a year later I found out that he had been having an affair with a girl our daughters age and they had a baby. It broke me in ways I'm still trying to understand.He denies having anything to do with her but I don't believe it. He still comes over and talk like we always did. I just get hurt all over again whenever he's around but my heart loves him. I don't know what to do. I don't even know if he ever really loved me or if it just died.