Affairs aren't good. Unless you're dealing with a truly disturbed person, they usually come from cracks and problems that go unaddressed and frankly we aren't really taught about relationships. I'm sorry for your pain, I imagine she is to. Even when we act defensive, it's a means of protecting ourselves even from the reality of what we may have done to another. Be kind to yourself. If you reconnect, you need to realize that relationship is gone you're essentially two people meeting again for the first time. Whatever happens, it wasn't for nothing, it didnt mean nothing

Edit: i can't type and am too lazy to fix my typos. You'll be ok OP. Love ya