I've been in this place with my relationship before, having done regrettable things to my partner to hurt him. After 6 years of trying and failing to make "us" work, I've come to accept that we're vastly different, I have a lot to work on (which I cannot constantly make his burden) and so does he (which he does not admit). I let him go by understanding and taking to heart the sentiment that BonnieG2010 shared, which is, he is mad at me for things done 5 years ago, but is even madder at himself. Your reasons for letting go may be different, or may not be strong enough to actually let go, but if you focus on accepting your shortcomings and working on them, things will start to get clearer. Good luck, I really hope things work out for you