Most importantly, make sure you're clear about how you feel and what you want to say. "Once you ring that bell, you can't unring it," said Banks. "This conversation must be as careful and loving as possible."
Fitzpatrick encourages starting with the positive. "Express appreciation for the good things in your relationship," said Fitzpatrick. "Then you can say what you want to work on together. Make it clear that your goal is to make your relationship better."
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If your partner gets upset, stop the conversation before things escalate. Acknowledge that your partner is upset, but that was not your intention. "It's as simple as saying, 'I can tell I hurt you, and that's not what I wanted to do,''' Fitzpatrick said. "Tell you partner you care and want your relationship to be better, so you'd like to talk about it another time."
Give your partner a chance to cool off. Be sensitive when you bring up the topic again, reaffirming that your goal is to make your relationship stronger together.
4. Explain that this conversation is feedback, not an ultimatum.
A healthy "I'm no longer attracted to you" conversation isn't intended to make your partner feel bad. It comes from a place of love and a desire for things to get better. Ideally, a secure partner will see the conversation as feedback on your relationship, not something to take personally. Still, it's easier said than done.
"With something as tender as this, acknowledge your partner for even listening," advised Banks. If your partner asks for support in making changes, offer it. Otherwise, stay quiet. Your job is to address your feelings, not to tell your partner what to do or how to do it.
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Despite stereotypes that women are more concerned with their appearance than men, Banks said men have a harder time processing a conversation like this and tend to get more defensive when criticized. "When a woman looks at a man and thinks he's not attractive, it's not necessarily about his clothes or how he looks—it's about how he lives his life. Consciously or unconsciously, men know this," said Banks.