>>214015110 (OP)
Yes. Sex with anybody but each other counts as cheating, for either of us. And cheating pretty much always sucks. It hurts people you’re supposed to love.
A long time ago, before we were married, and not sure how serious we were, my now-wife and I didn’t quite break up, but decided to see other people (we were in different countries at the time), and even that sucked. I hated it when she did it, even though it was mostly my idea, and she hated it when I did it. We both concluded that we preferred each other and monogamy, and so it has been since. If she decided she needed to fuck some woman or other, she’d tell me and we’d talk about it. I don’t think I would approve, and if I found out about it after the fact I would struggle to forgive. Yes, even if I were invited—I tried group sex once and found it awkward as hell, and I don’t like to share.