Dave, real bummer man. Keep your chin up. I notice you say the two of you have been married for 17 years? That is a lot of history. If it was just one night and you love her maybe forgive her another chance? If you can't then maybe move on but of course put your kids first. I guess the most important thing is for you to decide what your going to do and then do your best to make that path right (hope that makes sense)