bpickle, I think there is still hope for your marriage. Don't let old baggage trip you up. It seems like such a waste if the only advantage of a new partner is simply that you don't share old baggage with that new person, even if that new person might have had all the same problems with another partner. So, yes, how can you erase the baggage and start over?
Feelings can change, and old resentments tend to diminish over time as long as they aren't freshly replenished.