How to remedy the situation and my mental wellbeing asap

Okay so basically to make this short, all of these events have happened between january 2023 and now.

Me, brother, mom, step-dad, dog, two cats living together. My mom dies in january. Living with pets, stepdad and brother. Stepdad doesnt like me anymore, we fight and he kicks me out in march, cuts phone, repos car, not allowed to take moms belongings. I go to live with my sister, have no contact with brother or pets for over 7 months then i gain permission to bring brother over forever the weekend sometimes. Not allowed to come in house to see pets. November we find out stepdad has been seeing a new woman for a few months. Brother and stepdad fly to LA to see biological dad, stepdad goes to see new woman in LA. Fast forward few months, slowly getting more of moms things. Brother is nearly done with school and stepdad decides he doesnt want him anymore to make space for new woman. This is current now vv Gives us 2 days notice (21st) to take brother and fly him out to LA to live with biodad. Wants to ship the dog off and put cats in the pound to get offed. (Havent seen them since getting kicked) We've had said animals for years and years now. Sister hates my cats, has cat of her own, wont let me bring them over. My cats are also not good with other cats. Have till the 21st to figure something out for them Before they get eu* No luck and ready to just about shut down

Basically how to be okay with having every piece of your family torn apart by one person so fast. Thanks