Dear Prudence: I'm a divorced father of a young girl, living in state A. Two years ago I met a wonderful woman online, in my same profession, who lives in neighboring state B, and we recently became engaged. I have a great co-parenting relationship with my ex and made clear from the start that I would not be willing to move to state B.

My fiancée assured me that this was not a problem as her ex was an absentee parent and she would be able to live in my state after she got court permission to move with her daughter. She would be giving up a very successful career in her state to start over with me. She notified her ex of her plans and he stepped up, going from 15 percent parenting to 50 percent.

Now he says that if my fiancée wants to move their daughter, the girl has to live with him during the school year and be with her mother during summers and every other weekend. My fiancée wants to proceed with this proposal. I'm struggling with this. Should I accept my fiancée doing something I find disturbing, leaving her daughter most of the year with her supposedly rotten ex, which I would not do myself? Or should I respect that this is her decision? I'm concerned she will get here and resent me for the inequality of the situation.

Prudence says: This really does require the judgment of Solomon, but all I can offer is my perspective, which mirrors yours. I can understand that your fiancée, having been so disappointed in love, and having found the other prospects so lacking, does not want to let go of the chance to be happy with you.

But I agree that happiness that depends on largely walking away from a child, and leaving her with an ex she thinks inadequate, comes at too high a price. I'm afraid that for the time being I think that you and she should be the people who make the sacrifice and do the traveling. Continue to see each other as much as your schedules will allow; maybe you can each work remotely in the other's state when you're off child care duties.

It could be that you can wait out the rotten ex, who perhaps can't sustain this level of commitment. I don't see how your love can thrive when your fiancée will have a hole in her heart where her daughter should be.

Send questions to prudence@slate.com.