Obviously we're just one couple and everyone is different, but we played with single guys when we were in our 20s--our early 20s, in fact. But then, we'd been together since high school, so maybe we were further along in the security and trust departments than many couples at that age might be.
Hell, if anything, the thought of Mrs. Leftcoast with a single guy was a bigger turn-on for me then than it is now. Not that it's not still a huge one--it is--but as I'm sure many guys who've hit 40 can relate to, I'm finding that things mellow a bit with age. So at this point, it's more of a slow burn than a crawling-up-the-walls kind of thing.