Why is he so upset when I'm the one should be mad?

My husband is upset that I don't believe in polygamy. He wants a second wife... I found out he was talking to his ex. She was telling him that she doesn't mind being around me and the kids. I told him that he can have her ans I want a divorce now he's angry at me. He's sending me angry text messages saying that I will never find a good man... and other threats.

Why is he so upset when I'm the one should be mad?
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