Help please

My SO cheated two years ago and I sometimes begin going through the emotions all over again like it just happened. I’m trying to find ways to cope, to let go, to truly release the pain and hurt that still lingers on. I’ll begin questioning if he finds me attractive, satisfying or even if he is in love with me. I will get really happy and the. Suddenly I’ll break. Which isn’t fair or healthy for either of us. I feel like a broken puzzle piece, trying to put it together. I will feel like I’ve forgiven him, then boom randomly I’m back a square one.