I do agree porn can be abusive and degrading to women (and to men in different ways) and the porn industry on the whole is vile. But speaking as a male who has huge issues with touch and sex often it just feels safer and less stressful to do it yourself, you also know how to touch yourself in ways that a partner doesn't always get, even the most sensitive and closest to you. And I know this is true for many women as well as men. I also do find that an erotic image/movie to focus on can help, I try to go for more sex positive feminist erotica than mainstream porn because of my views on the industry as a whole, it's not perfect but I feel guilt about sex no matter what I do anyway so there's no easy answer. So I can understand that it doesn't mean there's anything wrong in a relationship for a partner to also want to masturbate, it can make things better if acknowledged and even shared.