This sounds like a complex situation, sorry that you're going through this. The good news is, this situation won't last forever, luckily we're not living in a bad nightmare where every day is the same (although it certainly might feel like it now). I relate to some titbits you mentioned, it's super hard to get out of such situation. Being called "dramatic" for having emotions freaking suck, I assure you that how you feel is entirely valid.
Concerning validation, I really enjoyed hopping into this sub /r/emotionalneglect , you might find it relatable, it has a pretty decent community. - You absolutely don't want to feel alone in this, having some space to process this all is important, where you don't get invalidated.
I recommend looking for some resource on validating emotions, could be an affirmations app or a therapist's IG account for example, and write down what resonated with you. I found it deeply healing
A resource you might find useful at some point - it's typically for ppl dealing with someone with PDs, but I found it handy in general when it comes to dealing with difficult people (use with caution, it's better for self-awareness of what's going on and being aware of a potential future situation that will be your Family 2.0). https://outofthefog.website/toolbox-intro
Last thing, I highly recommend in finding actionable things to do outside your situation - give as little energy as possible to the toxic people around you (in practice, this means, instead of constantly focusing on the Now, the situation surrounding them, how to deal with them, thinking about them = giving it energy; think about yourself and your future - things you can do for yourself right now (can be as simple as, "what will I do in the next hour?", or "what do I need now, at this very moment?", you don't have to think big and far), and try to stay out of home as much as possible to reduce contact and have space to reset yourself, ...)
Also, idk if this is helpful for you now, it was rather helpful for me after I reduced the amount of sh1t in my life, but creating art and getting in your body is pure love when it comes to reconnecting with yourself.
Don't hesitate calling a help-line, they might have some actionable advice and ways to get you out of this. It's also way more powerful to speak to someone about these issues in person than over mere text.
... some of this advice's potentially bad, take what works, leave what doesn't. And no, most of the people out there aren't total assholes - keep in mind that abuse often happens precisely in close relationships like these. You are perfectly in control of whom you let it and who gets to stay out. Just keep in mind that you might unconsciously look for people who keep you stuck, who reaffirm your negative beliefs, and then your perspective becomes that - thinking that's all there is to it.