It makes sense, but I haven’t heard it explained this way before – the anger (due to infidelity) is there because they care. It takes a higher level of thinking to not throw away the entire relationship over an affair, but to look at it as a whole, and realize that the person you’re with is still a good person, even if they messed up in this one instance.
When she explains it that way, it really makes you look at how easily people throw away relationships these days (with our swipe-right, something-else-is-better-around-the-corner attitude) and you can’t help but think real love is dead. People throw away relationships for so many absurd reasons. It takes love to look at your partner after a breach of trust like an affair and be willing to say, “You’re a good person. You messed up. Now lets figure out how to move past this.” Sadly, it seems people throw away relationships because they don’t like the way their partner folds the towels.