Well - I have a slightly different perspective than Chatterbug.
Yes, I agree with getting your ducks in a row legally and financially. And yes, I agree with presenting things in a very matter-of-fact manner, if you do make that decision.
On the other hand - much as you might like the kids to know this is DAD'S fault, that he's a cheater etc - that has fallout on your kids and their relationship with their dad that may not be good for THEM.
My kids unfortunately knew their dad cheated on me, and the angst that that caused them and the anger they still have towards their dad over it, colors many things in their adult lives.
