Re: my story
I think your reluctance to file for D is from your fear of losing her income and the comfortable living you have come to enjoy. For this, she lost her respect for you and you want to hang on to this lifestyle no matter what.
Like your lawyer suggested, why don't you either get a job or go back to school? If you had been the main caregiver for the children, the chances are high that you will get more favorable custody and therefore CS from your W in the event of D. And, even some alimony.
Her saying thaf if you make her happy she will come back to you is an utter nonsense. She says she doesn't see any realistic future with OM, but this is not unusual. Many WW feels the same way too, especially when the OM is married. She just wants to keep her status quo with children by keeping you on the side, while having him as her "man" in her heart.
Have some respect for yourself and try finding some anger in you. From outside looking in, you do know how pathetic you look right now, don't you?