Dear Prudence,
I’m poly, and my boyfriend is not. This wasn’t a problem until he got back with his ex-girlfriend. He and I were together behind her back for some months, and it was a relief when he broke that off. It sounded like an unhappy relationship that dragged on long past its expiration date, and I’ll admit his recitation of all her faults and the miserable state of their relationship made it easier for me to be partner to infidelity. Then he went back after two weeks. He says he regrets telling me only bad things about her—evidently she isn’t as emotionally abusive as he let on, etc. I asked him if specific things he’d told me did not in fact happen. He made excuses. They would have a bad interaction, and he would feel disrespected, then within a couple of days the narrative would shift and he would say he needed to be more considerate and there is nothing to forgive, because nobody did anything wrong. It was super frustrating to watch.
But anyway, she’s back, and he wants to carry on with me like we were. Only she hasn’t consented to a poly relationship, and from what he has said, it’s not even worth bringing up the subject with her. I don’t want to give him up. I enjoy his company, and he brings a lot of joy to my life. But … the girlfriend! I know this isn’t ethical poly anymore, and I know what the right thing is. I guess I’m writing to you for a shot of courage. Any advice on how to get over how much this is gonna ache when I cut him loose? And how do I let him know that he has a place in my clan when he is free again—without sounding like I’m looking forward to this reconciliation falling apart?
—How to Exit Gracefully