I’ve posted before about my dsis dh’s affairs and him posting nude pics of himself to other women. They are now separated pending divorce. Our family is in pieces, they seemed so happy, he was such considerate, loving, caring husband, would do anything for my sister, he was the last person we thought would turn out to be a sex pervert pig. There was one woman who he had an affair with who contacted my sister to apologise. She said that he told her his marriage was perfect but he was weak and just a man, and she was beautiful and he couldn’t resist her. They are no longer seeing each other. My dsis is devastated, pregnant and in therapy. I don’t understand why he did it. Why do happily married people cheat? Especially if they feel themselves that their marriage is good?