My husband won't quit smoking, even though I now have health problems.

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Dear Prudie,
I have been married to my husband, whom I love dearly, for three years. The problem is his smoking. I knew he was a smoker when I married him (I was adamantly against dating smokers, but he was very persistent), but he would almost always smoke outside when he came to visit me. Once we got married, he said that he shouldn't have to smoke outside in his own house. I have had bronchitis three or four times in the past three years, and the doctor recommended I avoid cigarette smoke. I have tried reasoning, crying, screaming, and threatening, but nothing seems to work. I'm not sure if my husband doesn't believe that his smoking affects my health and eventually could kill me, or if he doesn't care. I believe he loves me, but he loves his cigarettes more. I will feel like an idiot if I have to divorce him over this since he smoked when I met him, but I am obsessing about getting cancer or some other horrible disease. What do you suggest?

—Coughing

Dear Coughing,
You are already heading for a horrible disease: chronic bronchitis. You will note this NIH Web site mentions that one cause of this illness is secondhand smoke. Show your husband this, then tell him that despite his addiction, you can no longer allow your health to be compromised by it. You may love your husband dearly, but he's a major jerk. As far as demanding the right to smoke in his home—what does he tell flight attendants? "I paid for this seat and I'm smoking!" I agree with you there is something crazy about contemplating ending an otherwise good marriage over his smoking, but there's also something crazy about contemplating a future in which you're attached to a rolling oxygen tank because of his smoking. I'm afraid it's time for an ultimatum. He takes his habit outside, or you take a hike.

—Prudie

Dear Prudie,
I just had my three-year anniversary with my boyfriend. He was married when we first met, and we eventually had a very brief affair before he left his wife. He has two children with her, whom I have a great relationship with and love very much. I am beginning to think it was a mistake and we rushed too quickly into getting serious. Now that we have settled into our life together (we bought a house), I find we have less and less in common and am starting to see that our long-term goals and dreams are vastly different. Thoughts of breaking up have crossed my mind. Although at the time I believed he left his wife because his marriage was over, I now know that I played a much greater role in bringing about the end of their marriage. I have so much guilt over how our relationship started and now feel even more guilt that I effectively stole someone else's life, a life that they wanted, and now I don't want it anymore. I also find it increasingly harder to deal with the fact that friends and family will always see me as the other woman or him as a scoundrel. I'm sure his ex would love to see our relationship fail as she hates my guts and I know that hearing about me from her children is torture. Sometimes I wish he would leave me and get back together with her. Am I entitled to familial happiness after what I did? I don't want to hurt him, and I especially don't want to hurt his children any more than I already have. I can't reach the decision to leave but am not happy staying. Is this my punishment for what I did?

—Guilty and Confused

Dear Guilty,
Imagine that you and your boyfriend were meeting now as single people—would you want to get involved with him? If you think back to when it began, was there anything drawing you two together besides the thrill of an illicit relationship? It sounds as if you wouldn't choose him now, and you're sorry you chose him then. That makes your current restlessness perfectly understandable. You wanted a fling. But flings have a way of setting off chain reactions, and his marriage blew up. And now—oh the irony—you are living the cozy, if dull, domestic life you both destroyed. Generally, I am in favor of people working on saving less-than-perfect marriages, especially if there are children involved. It sounds as if you have come to that belated conclusion, too, because you wish the time machine would whisk him back to his ex-wife. But you're not married and these aren't your children. It's good that you love them and don't want to cause more pain. But your letter leads me to believe you can't stay because of them, either. If you do, you'll probably just find yourself having another affair as a way of getting out. You need to make a real decision about what you want, instead of getting swept along by events. If you do go, it's unlikely he will get back together with his wife. It happens on occasion, but usually that relationship is so broken it can't be repaired. But if you want a little sop for your guilt, you're right that your leaving will make his ex-wife happy.

—Prudie

Dear Prudence,
I have a good working relationship with most of my male colleagues. However, recently I found myself uncomfortably but also undeniably very much attracted to one of my married colleagues. He and I joke around quite a bit because we both have an offbeat sense of humor. But then he asked me to go to dinner with him, just us. It was a very casual request in the line of, "We're both working late, let's grab something to eat ..." Now I can't get him out of my mind. Aside from the fact that he's married, he also works in the office next to me, and I cringe at workplace romance. What should I do the next time he asks me to dinner? And am I a bad person to be so attracted to a married man? I feel like a home-wrecker even though nothing has happened.