Your dad married another woman. I understand it is disappointing for you, but that was his choice.
So she’s now your stepmom. That was your dad’s choice as well. He knew when he married her that she’d have that role in your life.
Your stepmom ‘controls’ your dad. Guess what. That’s your dad’s choice as well. He’s obviously happy with that or it wouldn’t be happening.
So I’m going to encourage you to stop hating your stepmother. Why? Because I suspect she makes your father happy, even though you might not be seeing it.
If your dad feels comfortable being ‘controlled’ by your stepmom, you have to respect that. Perhaps he tells you he doesn’t like it because he thinks that’s what you want to hear. Or maybe you can see he’s fine with it but it just annoys you.
Either way, your dad has chosen to marry a woman you think is controlling. And yes, she may well be. But don’t hate her for it.
This is the woman who is likely to be keeping your dad company when he’s old and you’re busy leading your own adult life. It is good that he has a partner he loves who loves him. Even if she is controlling.
Please respect their right to have the kind of relationship that makes them happy. The time will come when you choose a life partner and you’re going to expect your family to respect your choice.
If your stepmom is not causing you harm, I can’t see any reason why you should hate her.