How Would You Feel?

If your other half told you they'd kill you if they ever found out about or walked in on you cheating?

I have never cheated. I have never had the intention to. Never even been a thought.

We were talking about our friends who are trying to fix their marriage. (She cheated on him for her reasoning of 'he was gone working all the time') I mentioned that I didn't think I could continue our relationship if he ever cheated on me because I'd be disgusted just by looking at him or thinking about him. He then said very seriously 'If you ever did that to me, there'd be nothing to work out, I'd kill you.' I was a little taken aback!

How would you have responded?