What a painful situation to be in. You can't let yourself be strung along like this - it'll ruin your life. How many years is long enough for her to figure out that she can correct the mistake she made?
You have to set a deadline for this and stick to it: no matter what. You'll go insane otherwise, or be one of those people who spends their whole life pining away for the "lost love". You deserve a full life with a woman who loves you and can commit to you. Being stuck in the middle is Hellish for everyone involved.
One part of this that you need to understand that feelings and behavior are two very different animals. You and your ex may feel all connected and loving, but both of your behavior isn't moving in that direction. This tells me volumes, and I'm not interested in all the outside issues. That alone speaks very loudly. You're both adults. If she wanted to be with you, she would have. If she wants to be with you and won't do it, what is the difference between that and the relationship you already had? She felt love, but her behavior led her to divorce you. She feels love now, but her behavior led her to divorce you and marry another man. She loved the other man and continues to court the other man as her husband. This shows an incredible self centeredness and inmaturity.
I'd advise you to set a date for one month and if she isn't out of his house and in yours, let it go and don't turn back.
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