Everyone so far has given great advice and I agree with all of it. If I were you I would say this to her,
"sweetheart, I'm changing the locks tomorrow so you better get what you need and leave. I will be filing for divorce as soon as possible and will not support you one moment longer. Tonight you can sleep on the couch and I will have the bed. Further more I suggest that you take a long hard look at your relationships with people as I think your cheating ways will catch up with you and you will die a bitter old woman who has never given in order to receive love."
I would take the time to be sure you know what your rights are before hand and be very sure you are ready as she sounds like a fighter who figures the world owes her something.
I am sorry you have experienced this kind of abuse, it is abuse to me, but you had a part to play in letting her walk all over you. Don't do it again! No one should ever let anyone for one second feel they aren't worthy of love and respect. Once started on that path it is hard to come back from it.
Make sure that this next woman treats you with respect and that you do the same. If she doesn't then get out fast. You will be sad, but it is so worth what it does to your self esteem. Hopefully you will see that as you blind side your wife and upturn the hurtful, self centered, selfish, cruel and self righteous world she has been living in.
I would love to be there to smack her up side the head personally, not to mention the man she calls hers and has the gaul to call her boyfriend. What is that? It degrades the word! It discusts me to no end the pain people cause one another. Really it does!
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