Fear. Fear of being cut off from their judgemental families and culture. Period. Libs will mock anyone seeming to stray. You have to be strong and call them on it or ignore it. Most people wouldn’t. And it is true, once you “come out” as conservative in a piously liberal extended family, they will all link every move you make to proof of your idiocy. It can mean losing an extended family. It can make you depressed about “family.”
This has all happened to me. It is VERY HARD to buck a cohesive group who really do love one another but not unconditionally. I understand why people don’t bother to stray outside the group.
I’m sorry to hear you’ve been through that. Libs can be very nasty when you pull back their masks. Have you found good conservatives upon whom you can rely for support and friendship?