A reader writes... Q: I’ve been married to a wonderful woman for five years and have known her for 10. She is fun, caring, witty, smart, interesting, and a great mother. I love her very much, but in the last several years our sex life has become nonexistent. This is partly because she is never the aggressor, and mostly because I have to admit I’m not physically attracted anymore to this woman whom I love. She’s not unattractive, although she has gained weight since I first met her (but so have I), especially since our child was born. How can I force myself to be turned on by someone who used to do so but doesn’t anymore? This must happen to most couples around the world as they get older and change — I guess it’s the difference between love and lust — but how do I stay faithful in a relationship if the attraction isn’t there anymore?

A reader writes...Q: My fiancee and I are in our late 20s. We have been living together for two years. I love her a lot. She is very intelligent, and I find her very attractive. The problem? Let’s just say that in bed, I have had better. Many of our sessions end without me “finishing.” She had noticed this and asked me if she still excites me. I tried to fix things by fantasizing about other women during sex, but that only worked a few times. Then, things changed on our last visit to her parents. I was blown away by her 18-year-old sister. She was wearing a tramped-out Catholic schoolgirl outfit. I immediately began fantasizing about her. The results were amazing. The last month or so, our sex sessions have been great. My fiancee has noticed the difference. She is now a detective, inquiring about the changes. I don’t know what to tell her. She once commented, when I asked her to dress up certain ways, that she could “just borrow these clothes from her sister instead of buying them.” Does she know seomthingsomething? What do I tell her if she persists? I worry that if I play stupid, she will grow very suspicious that I’m doing something besides having fantasies.

A reader writes...Q: I caught my boyfriend looking at Internet porn. It makes me feel like if I'm not good enough for him. How can I get him to stop?

A reader writes...Q: My friend likes to play tennis, and he’s good at it. A couple times a month, he plays with a female co-worker about his age who’s at his skill level. His wife is taking extreme issue with this. It’s not that he doesn’t want to play tennis with his wife, it’s just that he likes the better “competition” he gets when playing with the co-worker since his wife isn't a good tennis player. The relationship between the friend and co-worker is completely platonic. I’ve always known this guy to be honest and honorable. His wife is insisting that he either find someone else to play with (none of his other friends play tennis), or to stop the activity entirely. She thinks you just shouldn’t do “stuff like that” alone with a member of the opposite sex. Concerns about cheating have never been an issue before. Is the wife being reasonable? Or should my friend stand up for himself and tell her to get over her jealousy?

A reader writes...Q: I’m dating a guy I really like and want to give him a birthday present. I don’t know what to get. We’ve been dating six months. I don’t want to embarrass him, and I’d like it to be something he can use or really enjoys. Could you give me a few ideas?

A reader writes... Q: What's the one sure way to give my girlfriend a mild-blowing orgasm?

A reader writes... I met a girl a few months ago when visiting a friend. We hit it off and I happened to be passing through that town again so we saw each other again. It was a lot of fun for both of us and so a few weeks later I took the train and went to just visit her (the other times I had other reasons to be in town). She's said she really wants to come visit me but that was some weeks ago. We made plans twice but each time she had to cancel for what seemed like legitimate reasons. I've been in long distance relationships before and I know that unless you see one another frequently, the attraction can die quickly. We haven't seen each other for about 6 weeks now and I feel like that is happening. What can I do?