Dear Eric: I live with my partner of two years and his family (mother, younger siblings and mother’s boyfriend).

Yesterday, his mother confided to me that the violent, controlling man my partner knows as his semi-estranged father is not his biological father. My partner is not aware of this. I also don’t know if anyone in his family knows. The man who helped conceive my partner hasn’t been in the picture since before my partner was even born.

While I can understand that my partner’s mother trusts me enough to confide in me, I didn’t want to know this information, and now that I know, I wish I didn’t know. I don’t plan on sharing this secret with my partner because it’s not my place to share, but it also doesn’t seem right to me to keep it from him.

I also worry about the potential consequences of telling him now or letting someone else know later (especially if my partner finds out I knew but didn’t tell him). I don’t want to hurt him, and I don’t want to harm our relationship or the already complicated relationship he has with his mother. I would love to hear your advice.

– Not my secret

Dear Secret: Your partner’s mother put you in a terrible situation. It wasn’t appropriate and for you to move forward in a relationship with her, she needs to fix it.

Talk to them privately and share what you shared in your letter: You don’t feel comfortable keeping a secret from your partner, especially this secret. And for the sake of your relationship with your partner, you won’t do it.

Then ask her how she plans to talk about it with him.

Your position must be clear and firm. If you keep this secret, it may irrevocably damage your relationship with your partner.

She may not feel like she has anyone else to talk to about this. You can show sympathy and love, while making it clear that a boundary has been crossed and you need to fix it together. Keeping this secret can also create a toxic situation in your living environment if this problem is not addressed.

Find out when she plans to have the conversation. It shouldn’t take long. In the meantime, start thinking about how you will talk to your partner next. It’s important to remind him that you’re there for him, that you’re sorry you found out about it before he did, and that you’re available to help him deal with any conflicted feelings he has about it.

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Send your questions to R. Eric Thomas at [email protected] or PO Box 22474, Philadelphia, PA 19110. Follow him on Instagram and sign up for his weekly newsletter at rericthomas.com.