If, somehow, your marriage could be saved, and made workable, mediocre and somewhat fulfilling -- if not spectacular -- and your kids would have an unbroken home, would return to it if you felt that you could have a terrific relationship with someone else? Would you settle for a lack-luster marriage with your current spouse if you somehow knew there was a good shot at a great marriage with someone else?
With kids involved, I would in a heartbeat... they are blameless, and deserve the absolute best we can offer.