You both have been very wounded in this marriage and that's a shame. It's great that she now doesn't regret it all, b/c of the kids and I think that is healthy. I hope the kids will always know that they were the reason she hung in there so long, and the reason you are trying now to keep it together. (IOW, They are NOT factors in the marital problems)
I think you have to stop the pursuit but I also don't think you will take that advice. so it's more damage control than a real strategy now.
Just try to show her she can relax around you and you do that most by NOT having any expectations of her, at all. Just enjoy the evening together. It's okay to discuss the kids (being the best father you can be to them is a HUGE factor in your favor so don't skimp on that!)
but make sure you also connect on other levels. Ask her questions about her dreams and ideal career goals and anything OTHER THAN OM or his poor wife...
Clearly, your w wants an equal partner in the financial responsibilities area, so I'd project the attitude of a man who :IS more career oriented than she sees you as being. Admit your priorities needed changing and HAVE BEEN CHANGED and you look forward to the advancement possibilities you see at the new job (and remind her that you DO Value her input and insights and will probably discuss those things with her in the future as it benefits your chidden and each other...and leave out talk about the future. Read those newbie "Rules" again if you must.
Compliment her authentically and specifically BUT then move on in the conversation , don't act as if you are waiting for her reaction/gratitude etc. Again, no expectations. Just a fun easy going night at home. The more relaxed around you she can be, the easier it'll be to spend time together and maybe build on that.
It seems to me that career ambitions are one of the attractions she feels toward OM. (What do you think she meant when she said you and OM's wife are alike?) And though you put her thru hell awhile back, ( & more than once), at some point you will need to be LESS available as her back up plan.
Ask your DB coach for more advice about that^^^ and her "Long term plans"...
AND please take the advice given to you by the DB coach, or at least don't blame the DB approach for not working - when you are not working the DB program.
The program can work IF you work the program. Make sense?
Good luck.
M: 15 years BD: 6/25/14 EA/PA: starts 5/14/14 11/30/14 - A ends 5/15/15 - D is finalized. 11/28/15 - Start of new LTR with a wonderful woman (and still going strong)!