I would talk to a C about your D. She's using her to get at you which is extremely damaging to her. Your W's using her to get under your skin, but in the end your D is going to be messed up and think oh it's cool for mommy to have a H and a BF.
Screw that. Get your W away as quickly as possible. Do it very calmly so that it seems like you're taking care of business instead of reacting to her. When she goes off, don't say anything. You're done talking to her after all and she won't listen to anything you say anyway. Just look at her like a spoiled brat. A pitiful creature.
When you stop reacting to her and do your own thing, she's going to break. Once you are gone, she won't have any choice but to see what she's doing.
I would seriously look at getting primary custody too because she's going to fill their heads with all kinds of venom that will hurt them in the end.
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.