"Our plight as humans might be that we are condemned, in virtue of our attachment to life, to affirming conditions in the world that we cannot possibly regard as worthy of this attitude. There is something absurd about this situation, involving as it does the persistence of attitudes that don't fundamentally make sense to their bearers. But the absurdity may be one that is endemic to the human condition." pg. 204
In The View From Here, R. Jay Wallace does a decent job of discussing issues of regret and reconciling wrong past actions with the present. Such discussion is worthwhile, as it fills a hole generally avoided in philosophy: how do we deal with bad actions when good arises from them? Wallace admits from the beginning that he doesn't have a good answer to this question, eventually settling on what he calls "modest nihilism" which can basically be translated for the common man to "shit happens". This explanation is certainly unsatisfying, but Wallace still has a great deal of interesting thoughts on the subject, enough for a worthwhile book. Still, I don't believe it'd be too much to ask for a few more grasps at a grander theory rather than end on a shrug.