Hey Del. Perhaps if 'this is the way things have always been done' in your family, everyone has 'adapted' to the status quo and rocking the boat by doing something different is too confronting for them.
It sounds like you were taught that you don't have the right to stand up for yourself. And that your family 'believes' this. but it IS okay for you to learn something different, even if they don't agree with it. Even if they continue to behave the way they have always behaved. That doesn't make them right: it only makes them entrenched in their own abusive patterns of communication.

One thing that works for me when dealing with people like that (my own family, lol) is just being a broken record. I love the broken record technique because it doesn't require me to think of anything different to say - I can just stick to repeating "I don't like being spoken to disrespectfully and I want you to stop". They can come back with as many variations of their crap as they like, but the bottom line is, I don't like being treated that way, and I want them to stop.
Eventually they stop. I spose because they are not getting anything out of it. LOL.
The other thing I like about the broken record technique is that it allows me to remain true to myself. It allows me to stand up for myself. And it allows me to send them a very strong message that I am not going to engage with them in their crap, and I am not going to take on their crap, and what they are doing IS, in fact, crap.

You really don't have to take their crap. But I do appreciate that it is a huge thing to unlearn after years and years of being on the receiving end of it. Keep working at it, eh?