A couple of things come to mind when trying to explain married men's attraction to single women.
1. An episode of Phil Donahue decades ago dwelt on the problems newly-divorced women had dating. One said "Sex." Another chimed in, "They think you've been without it so long you can't wait to drag them to bed." So some of these men could assume you've had a long nasty battle, and you're as horny as they would be after that time. What they don't realize is that for a variety of reasons, women can go without sex for long periods of time and not miss it as badly, if at all. It's not like food, after all.
2. Kinda ties into the last part of #1. I've read that "evolutionary biologists" theorize that men sought multiple sex partners in caveman days as a way of insuring the bloodlines continued. in the religious area we see this in the societies that allowed polygamy or polyamory. The point being that we still act based on those ideas.
3. The guys are responding to a mid-life crisis. There comes a time when we look back at our lives and ask ourselves, "What have I done?" And for many this is an incredibly depressing time. They think of the paths not taken, the job choices or other opportunities missed, and their declining youth, and they overreact. Buying a sports car, taking up dangerous hobbies, affairs are some ways they handle it. I'm not saying that excuses their marital wanderlust though. And though someone could tell them about the uselessness of hindsight in such cases, it doesn't matter. Sure, we didn't know then that had we done this or that things would have been different (i.e., better) but we know now.
4. Ties in with number three a little. Are they still "virile?" Do women still swoon over them (failing to notice the vast majority never did anyway)? And so you're both a challenge and an opportunity. Maybe even a conquest.
I had a divorced woman hit on me once (though I was too shy to recognize it). This was when my wife and I both worked at the same place (she and Lady X are both nurse adie's). She told me she was divorced, showed me a pic of her ex and their daughter, and put her hand over mine. I didn't respond, and so she soon lost interest. I was vaguely uncomfortable but that's long past.
Well, this is more than a couple of things, =:0 and some may see flaws I've overlooked. And the old "My wife doesn't understand me" line still makes the rounds as far as I know. Plus that old saw about the grass being greener somewhere else.
As far as signals you could be sending unintentionally: what guy doesn't like talking to attractive women? Just being there could be enough for some guys. Now, where I work, the amount of openly expressed sexual desire is making us a legend in our county. Several women got into a discussion one night while labelling boxes on the topic of--penises. Nobody's in particular, though there was speculation about one guy on Sanitation who'd make a horse feel inferior. One of the older women had to complain to get it stopped. The atmosphere is sexual to some degree with many. Anyway, looks, comments (out of earshot) are made about one supervisor when she comes in during our lunch break (5:30-6:00 AM). Our resident accountant many times wears SHORT culottes and so on (and has the legs for it, I'll admit). The first one isn't doing anything I can say is out of the ordinary--she's attractive, smiles, isn't going to change how she gets to her work area because of us horny perverts, and so on it goes.
