Friend's Possessive Husband

I have a close female friend from school. We were very close from childhood. Two years ago, she got married, and she did say her husband is possessive many times. Recently, she stayed at my place for a couple of days for her work, and we didn't even touch each other during her stay. We slept in separate rooms. We went out with our common friends, took many pics, and posted them on social media. She hugged me and left after 2 days. Two days later, she said her husband is asking her if she slept with me. This is common, but he did cross the line as he called me and asked if I banged his wife (my friend). I got frustrated, and I told her we need to do that for real to teach him a lesson.

I dunno what state of mind she is in; she said YES. Is it morally correct to bang my friend who is married?