Quitting porn was very difficult for me in the beginning. I went from wanting to relapse probably 50 times a day, then to a few times a day, then every day, but only a few times, then to days between, then a week, two weeks, three weeks, and then months between. I never will relapse now, it simply is not an option anymore, and though, yes, from time to time an image or thought will trigger me (which will always be the case), I have months between those uncomfortable but no longer challenging moments. The point I am making is, if you can get past the hard 90 then the longer you go the easier it becomes. Getting a dopamine high through exposure to porn is a learned behavior. Because of that, it is a behavior you must understand can be unlearned.
Good luck on your journey.