My parents are divorced now but there was a 6 or so year period where my Mom was fucking the pastor of our church and my dad was sticking around for the sake of the kids. It was absolutely awful. My Dad was miserable for years, my Mom was absolutely horrible to him and he just took it until he met some crazy lady at his high school reunion, had an affair of his own and divorced my Mom.
The end result is that now my siblings and I all love both of our parents but none of us respect either of them and we probably never will. If my Dad had put his foot down earlier, a couple of things could have happened. It could have snapped my Mom back to her senses and they could have rebuilt their marriage without the piece of shit pastor tagging along as a third wheel. The marriage could have ended (sooner than it did, of course) and we could have had at least one functional parent who didn't make a shitty choice and alienate us.
My point is that if what your kids are going through is anything like what my siblings and I did, you aren't doing them any favors by preserving the status quo. You may be keeping their two parent home intact but you and your wife are also modeling extremely poor behavior for them. Her for obvious reasons and you because you're showing them that it's best to appease and be walked on when someone who is supposed to love and cherish you is treating you like shit.
I've never met you but I know you deserve better than that and I think your kids probably do too.