Yep -- and the "eros" love toward a spouse is physiologically blocked when one is in an affair with someone else.
Oh I don't know if that's true.
It is. Read up on it. Formerly wayward spouses on these very forums talk about how they SAW their spouse's changes, and their loving gestures, but they were blocked from feeling or appreciating them, because they were infatuated with OM/OW. Just google "PEA" "brain chemicals" "love" "lust" sometime, and follow the links. It's truly fascinating stuff. It's what made an intelligent, otherwise sane adult female astronaut drive across country WEARING AN ADULT DIAPER, rather than stop for bathroom breaks, so she could drive to Florida to avenge her man!