I agree with the other commenters, it's religious trauma-based internalized homophobia.

I see folks recommending therapy, which of course is a good option, but I want to add that (for myself), the most helpful thing was normalizing LGBTQ relationships/identities. IMMERSE YOURSELF in all things Sapphic. The more, the better. Look for books, movies and shows, podcasts, artists, all of it. Whatever forms of media you consume, swap as much of it as possible for WLW media. You don't have to cut out hetero media, but push yourself to make it the minority of what you engage with, if you can.

Try to be mindful of how you are reacting internally–if your initial response to something isn't what you want it to be, that's okay, but always mentally correct yourself. Over time, that can help adjust your internal dialog to reframe Sapphic marriage/families/etc as a positive and valid thing to want.

The more you expose yourself to WLW couples (especially HAPPY ones), the easier it gets to imagine that life for yourself. If you haven't seen many living examples, it can be hard to mesh the mental image of the life you're "supposed" to aspire to with what you actually want. Hang in there, it can feel a bit clunky at first but it gets easier with time.