I guess I'm in the camp that holds that forgiveness and giving chances are separate issues. I can forgive someone and be well aware that they are not strong enough to stop whatever it is they did that caused me pain.
My aexh was not really aware of the effects of his addictions. He was hurt and angry at being held accountable, and he couldn't see beyond that. It seemed to me at the time that he didn't want a second chance, he just wanted things to go back to the way they were. (Now, I'm not so sure that it was so black and white, but I still think the principle is the same.)