I think it might help you if you focus on what you want in your own relationship(s)--this or any other relationship. I knew someone like you describe and he told me some of the same stuff you have listed here. I don't think he meant me any harm, but he was going to have other women in his life and that was it, and it did upset me. I didn't want that. End of story. Sometimes we meet really great people who are wonderful in many ways, but also, at the same time, there are deal-breakers connected to being with them. I get the impression this might be the deal-breaker for you, and if him seeing a gaggle of other women is distressing to you, maybe it should be, and you should move on to someone who is sincere about committing to you, and you only.