Firstly, calm down... Your sitting in a very good spot if she hasnt hired a lawyer. It means shes not as serious or determined if she had. Mine has a lawyer. If you really care deeply about your kids, treasure this time with them. You can see them any time you want. Read them stories etc. If you do split, that will be gone at least 50% of the time.
Its been said that limbo is the gift of time. You have a chance to turn it around. If she divorces, it becomes harder to do. IMO. Again, dont do her work for her. Passive resistance.
Not to upset you, but asking her if she is having an affair is pointless. I confronted my wife at OM1's door and she still denied it. Untill I was moving to knock on the door did she finially admit it. Read sandi's posts. To me it seems to coincidential.
Trust me, it adds a whole new level of anguish finding her leaving the house with toys and lube to meet OM. It does make you question if DB is really whats needed.
Take care man. One day at a time, and remember, it wont always be like this.