Most Helpful Guy
Well, if you have pushed them away by whatever means then your forgiveness is perhaps only relevant to you. They might not much care if you forgive them, they may feel that there is nothing to forgive.
I think we have to take ownership for what we do and expect that others do the same. Don't take all the blame on yourself if it wasn't all your fault, but recognise when it was mostly your fault and try to be better. As for forgiveness, if you feel you still have resentment in your heart then you have to let it go if you want to be back together or you want to move on. If you hold on to it you'll be poisoned by it.
Most Helpful Girl
Not everyone you meet is going to be with you forever. I would be grateful that he left before we were married with kids. You need to be with who you want to be with in life, I wouldn't hold it against him but I wouldn't blame myself for it either.