I’m a monogamous man and have been in a faithful relationship for the past eight months with an openly bisexual woman. Recently she admitted that her fantasy was to have a threesome with a guy and a girl, and she wanted me to be the guy. I won’t lie—I was flattered. But I was also hesitant and didn’t think I could go through with it. She really wanted to and assured me it wouldn’t be cheating and I’d enjoy it, so I decided to go along with the threesome. She brought a very beautiful friend of hers into our bed for an evening. Now the problem is my girlfriend wants this woman to join our relationship, making it a ménage à trois. I don’t know if I’m ready for something like that. After the three of us had made love, my girlfriend complained that I’d gone down on the other woman twice and had fucked her one more time than I had my girlfriend. We both like the woman, but I’m afraid adding her to our relationship will drive a wedge between us. I think I love my girlfriend, but she’s already showing signs of jealousy. I worry that if the three of us commit to one another, things could get really complicated. I don’t want to lose either of them. What should I do?J.T., Miami, Florida

Many men dream of having a three-way, but your story is one of the numerous cautionary tales we’ve heard about the fallout from an ongoing ménage à trois—particularly how it can negatively impact a long-term relationship. When you have a three-way, you get more than three-way sex; you also get three-way resentment, three-way jealousy, three-way differences of opinion, three-way split attention. You should share your concerns with your girlfriend. Tell her you don’t want to lose her because of the introduction of a third person. If she doesn’t mind risking that, you need to ask yourself what you’re willing to accept from this relationship and decide if it’s the right one (or two) for you.

This question is from the DEC 2014 issue of Playboy. To read the rest of this Advisor column, click here.

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