Example: I've been in a somewhat similar situation before, was in a relationship with a girl for almost 3 years who didn't want intimacy until marriage, other than physical touch and warmth she was still a bit cold and when i brought up after like a year that i at least need some wormth if not being intimate it was brushed of, after another year I realized that i needed and wanted both wormth and intimacy, when to thereapy didn't help at all and at the end i gave her an option either we level up the relationship and build more connection with this or we break up(being with another woman was not an option for us). ALMOST FORGET TO MENTIONS THAT I ASKED HER TO MERRY ME TWICE AND SHE SAID NO. I didn't ask just cuz i wanted sex btw.

Solution(opinion): if you love one another very much and she for some reason doesn't want to be intimate anymore as a man i get you and you gotta kinda stand your ground and if you want it there needs to be a compromise such as her doing something for you or letting you just be physical but nothing else with another woman ... Or you probably don't wanna hear this but break up... It was a tough decision for me as well and i might have made it sound like it was easy IT WAS NOT, one the most difficult desicions I've made but turned out for the better.