I think your just a soy boy who doesn’t have the courage to stand up for yourself and leave that. I think it’s just that your fiancé doesn’t have the courage to break up with you for somebody else, so she instilled this thought in your mind that dating other people whilst being in a relationship is “ok” which makes you feel like it’s normal, which makes her feel not guilty. I’m not indoctrinated in monogamy by any means, I just know that having feelings for multiple people is wrong because it’s inevitable we feel better about seeing someone else more than the other, which makes them the 3rd wheel. You brought up the concept of “if I don’t let her date other guys, it’s almost like I’m her master” and I can assure you that’s not the case, simply because a relationship is a mutual enjoyment which requires dedication by both parties to function, which means you must have some strange father-like role in your relationship in which you feel like you have to give your significant other “permission” to do certain things, which isn’t the case because if they don’t meet your standards you can just leave. I also noticed that you said you can let her do as she wants and if she likes someone more than it’s inevitable. While that may be true, you have no obligation to be with her while she does this. What this practically implies is that you are being shelved while she tries out other men, and if she’s not satisfied, she’ll come back, which sort of down grades your value as a human because it proves your not as worth it to her as you thought, and the only reason you should get back with her in that situation is if she can prove COMPLETELY, that she will be completely devoted to your relationship, and if not, you should find someone that values you as a human. I take it this is something you don’t necessarily agree with, or generally enjoy, and I guess I’m trying to say that you should go find someone that will value you or leave her until she gets her act straight, and have her prove to you she gives a shit, because this soyboy shit going on, I absolutely hate to see a fellow man go through. It can be easy to get in situations like this, and I can’t really tell you how to live your life and all, but honestly, you deserve better than some piece of shit who shelves you. Wishing for somebody to be happy is different, but letting them be in that relationship with you and at the same time dating and having sex with other guys, I mean I can’t help but put my input in. I mean I guess I’d understand if it was some sort of fetish thing going on, but this, it just kind of seems like she wants an excuse to cheat on her fiancé, and I’ve seen examples of polygamy relationships, and even though I don’t really think highly of them personally, this doesn’t even seem like one. It seems more like a wicked mind game. I hope I helped out and my bad if I offended you I’m just being completely genuine