Old married lady here.

Masturbation and sex are two different things. One is intimacy with another person, the other is intimacy with yourself. Mastication is a natural and healthy activity for men. You should also be masturbating regularly for your own mental and physical well-being.

People who shame their partners for masturbating are, in my view, emotionally abusive. You are not the owner of his body, nor is it your role to fulfill every one of his sexual needs. To assume that you do is a great conceit.

Your body is not perfect, nor is his. I doubt you expend much energy looking at men who are fitter and thinking that your husband should be replaced, so why would you imagine your husband is thinking of replacing you when he sees other female bodies?

As for the porn, my opinion is 'moderation in all things'. The fact that you spelled it ”p*rn” in your title makes me think that your view of it is not a moderate one. Porn is not a bad word. It is simply a noun.

It is also a legal (hopefully) and common means of getting off for both men and women. As long as he isn't replacing a full sex life with you with porn, then it is not really a big deal. If he is obsessed with daily porn or collecting a lot of specific porn, then I think having a talk with him about moderation is a good idea.

You are free to express your sexuality in your own way. For you, sex with your husband and no masturbation has been enough. But for him the frequency is likely not enough and he also is looking for personal sexual time. Do your libido a favour and spend some time exploring your sexuality alone, too.