we must bare in mind this woman was my best friend 8-months ago we did everything together.
Mark, again I want to say I think you are doing great in so many areas. See here is the thing best friends don't betray one another like your wife did. They also don't have full blown affairs on a whim. She probably wasn't happy for months but more likely years. IMO she is taking the easy way out because marriage is hard work.
With time and distance you will come too see this and she will slowly come down from the pedestal in your mind.
BTW I think your a fuching great Dad and your kids will always be closer to you.