I've been pondering on this matter for an hour: how could you have forgiven Dawn, if you can't forgive yourself?
There's a Buddhist praper of forgiveness, in its final verse, you ask yourself for forgiveness.
When I had my soul shattered by Katya, the most difficult part was forgiving myself for failing to get her. Took me a year, until I was finally able to let go of her and move on with my life. I hope it takes less time for you.