Jennifer asks: "I need tips and hints for an attraction I have to a co-worker that's married. He's made comments to me and to others at work that things are not great at home. I don't want to be a home wrecker but I also don't want to pass on a chance with a great guy. We've only flirted with each other, nothing serious has been said or done between us."
Jennifer, I'm going to be frank with you, and I'll hazard a guess you won't like my response by the way you've phrased your question. But here it is: there are oodles of single, available, attractive, 'great' guys. Why would you put yourself out there for someone who is obviously, completely unavailable, and may well only remain that way?
It sounds like there is a lot going on behind the scenes with this gentleman, most of which already says a lot about who he is, and what kind of person he'll be in a relationship: he openly talks to coworkers about his personal issues (would you want him to blab about the two of you at the office?), and he is using the attraction between you to take the edge off of the unhappiness in his marriage (would you feel comfortable if he flirted with other coworkers when things were rough, if you ever got together?).
Even so, he's otherwise spoken for romantically and sexually. You've stated you don't want to be a home wrecker - so don't be. If his marriage ends, let it be for its own reasons, instead of outside temptation. If he does separate from his partner, and if you're still single a year after that happens, then you can think about acting on your attraction. Until then? Put him out of your mind, ponder why you'd choose someone who is unavailable, focus on the things that make you feel amazing about yourself, and work on meeting someone and/or attracting a guy who is ready and able to give you the kind of relationship you deserve from the start.