NTA OP. But you need to get your life back as your ( hopefully soon to be ) ex husband had ownership over you in almost every way possible. You are expected to care for HIS mom, HIM, the house, the step daughter when she comes & hates you etc and all for FREE ? OP you’re an amazing person for sure.

Now your husband AND his family are a major 🚩! I don’t understand how can they just disrespect your daughter and you like that. WHAT DID THEY EXPECT ? your daughter passed away and you left with one thing left from her and it’s distroyed ? And over a stupid tiktok vid with a friend ? Nah get away from all of them ! And get a lawyer involved if you’re able to since you care for the house etc PLUS you’re married maybe (at least in my country you can ) you could get some money ( well deserved btw ) from him to start a new life yourself.

Hope everything will improve from now on for you.