And try not to spend your mental energy deciphering his odd and inconsistent behavior patterns. Was he using you for sex? Probably not, given such very infrequent sexual encounters and his later claims that he had doubts about his size etc. Was he using you for something else, such as to bolster his ego? He probably was. But you are not paid to write and defend a thesis about this man's motives and motivation.

I would also rejoice that you can end it early and walk away relatively unscarred.