OP, sending hugs. Your experience, or at least the scars it left on you, sound very similar to mine: eating disorder, lifelong massive generalised anxiety; and crippling social anxiety, feeling empty, terrified of being a burden if I ask for help, feeling unworthy of love or attention. And as if life is a game in which everyone else knows the rules and I don't.
You have CPTSD and although you're conscious that your parents were abusive, you're still not emotionally free—hence your desire not to "embarrass" your parents, and your feeling that you're still not "you."
And the shame, as if it were somehow your fault. It's not, it's all theirs. Having had a horrible childhood is no excuse to treat your own children the same way—it's possible to break the cycle. It's unlikely your parents will see or feel guilty about treating you so badly, far less apologise: they'll probably try to justify it by blaming you.
It will probably help you if you can find your anger. You were a small child who deserved to be treated with love and affection and to have your needs met.
The more people you can tell about it, the better for you, though a lot of people with normal loving parents won't be able to get their heads round it.
Some people who feel like you are helped with medication (doesn't do much for me), some by therapy, but it needs to be trauma-informed therapy.
Or you could try reading about it: there's a lot of material online, and some good books: Bessel van der Kolk's The Body Keeps the Score and Pete Wells' Complex PTSD: From Surviving to Thriving are good. Or watch Gabor Mate and the Crappy Childhood Fairy's videos.
Then there are the Stately Homes threads on Mumsnet—you described exactly that phenomenon—"How can you claim we were abusive when we took you to stately homes?"
But it's love children need, plain and simple, not holidays and horses.
Dealing with this is a long slow process: it can take decades even to realise the problem was them, not you, just what aspects of your life weren't normal, what you've missed out on and will never have now, the skills you didn't learn, how your experience taught you that people aren't safe and you can't rely on them. But progress and at least some healing are possible.
Sorry for the epic post!
Edited to fix typo