Kick her @ss to the curb and try to get custody of the kids. And I don't want to hear about how men never get custody...yadda..yadda...
If your w fights you on this, feel free to let her know that in addition to the OM and spouse, you will let her parents, other family members, friends, etc know about her degenerate, depraved behavior in the marital home. ICK!!
And I don't want to hear about how this will "make her mad" or "ruin any chance of reconciliation......yadda.....yadda..."
If you think that this sort of exposure is embarrassing or "fighting dirty," so be it! Your kids should be first and foremost above anything else.