That's real anger bubbling up. You have the right to be angry.
We have the right to be angry, especially at our parents for not protecting us. In my case, I am also angry at my parents for 1) not protecting me; 2) denying that it happened or could have happened, even when I've tried to talk to them and ask them about it in recent years; 3) holding me accountable for the effects of the abuse (including the emotional disregulation), as if it's my fault this is happening to me...
But I digress.
I also understand the desire to not upset our parents, especially with the knowledge that they love us and we need them. Even still, if it's bubbling up when you're around them and it needs to come out... talk them about it, use words and stay calm. Talk yourself through it, if you can.
I'll be just fine and dandy
Lord, it's like a hard candy Christmas
I'm barely getting through tomorrow
But I won't let sorrow get me way down.