tinman, i'm so sorry you have to go through all this in your life. you are in a h3ll of a spot. right now, i think the focus should be on your daughters.
you asked how your W could "cast us aside like nothing". i can tell you my experience and maybe you will have more insight.
first, you have been married a short time. your wife may be thinking that if this is what life with you is like, she needs to cut her losses now and get out. too much drama. as much as she loves you, the life you are offering her is too stressful.
i've been married for 15 years and the "crap" that comes with my H's adult children (especially, his daughter) and his family make me question if we could ever make a M work. i've just gotten to the point where it's not worth it. and that's after a long history together and still loving him.
your W sounds like she still loves you but she loves herself, too. it's too much sacrifice for her to be with you now.
my suggestion is to get through all your custody issues before you try to have a R with ANY woman. at this point in your life, with what you have going on, it's just not fair to ask another person, especially one with her own kids and ex, to take on all of this and try to be happy with you.
what you're seeing is why subsequent marriages with children fail so much more than first marriages. it's very, very hard.
i wish you the best.
((((()))))
M:63 H:53 S:41, SS:28, SS:25, SD:23 M:15 T:16
Bomb:12/17/11, "I think we should go our separate ways." H moves to his mother's house, 4/1/12 12/21/12: H moves back home, piecing