If what you're saying is right, then her decision to tie anger not actually derived from his sexual decision (the reasonable decision to enjoy porn, something humans have enjoyed all of history) constitutes an unwarranted and unjustified attack on his sexual being and very own biological autonomy. To disingenuously attack someone's sexual self-expression is a serious and disrespectful act, nowhere more so than a relationship.
If, on the other hand, she was indeed so hurt and furious about something so utterly banal and inoffensive as jerking off to some internet porn, particularly while they aren't even having sex, shows that she has seriously deluded and juvenile views of sex and relationships and that she needs to try to come to grips with the reality of the world and the fact that the porn wasn't hurting their relationship, but rather her reaction to it was and is.
Women who can't accept their husband or boyfriend enjoying pornography can never have a totally honest sexual relationship. If you don't like it, you can still choose whether to accept it, and let him enjoy something that makes him happy and thus a better partner, or you can refuse to accept it, and make him wade through the indignity of pretending not to enjoy pornography.
Either way, there is absolutely no way in hell that you are going to say or do anything that would lead to him suddenly not enjoying and consuming pornography. Which is not a problem because if you have any appreciation of the significance of your own sexual (and non-sexual) relationship, pornography should be about as much of a threat to your relationship as breakfast cereal.
A healthy enjoyment of porn never ruined a relationship. Psychopathic jealous lunatic women have that angle covered plenty well.