I don't think most women would flip out if they found that their partners looked at porn on occasion. But the situation you described is different.
I will say that even when my W found out about it the first time, when we had only been dating for a year or so, she was extremely upset then, too. I don't blame her, I'm not saying she's wrong. I agree that it is very wrong, I always have, even while I continued doing it. Just saying here that it is an even bigger deal to her than most women.
Me 38, WAW 30 D11 (former marriage) S2 T 8 years M 3 years BD 8/20/23 S 8/20/23