"S" might be able to separate sex from love, but he can't see how it hurts his fiance. So he appears immature. Also, when guys get married, they often feel trapped, like they have to sleep with a bunch of girls before they get married, because they will be "stuck" with just one after marriage. If the guy feels like they will be "stuck" with one girl after marriage, they are probably not sexually compatible. It usually boils down to sex. Most girls, especially younger ones in their 20s and 30s, have huge sexual hangups, it's a major problem. Just based on my experience. So girls, if you want to keep that guy, dump your hangups and preconceptions about sex. It's a good start anyway.
Or "S" might have poor impulse control.
It might even be that the fiance of S is not sexually compatible with S, so S should not get married, but feels pressured to do so. But he's afraid to break up with his fiance. He might even be afraid to admit he made a mistake getting engaged.
Keep in mind that many "hot" guys (and girls) sleep around, they know they are hot, so they have no need to committ. If you date a hot guy, you can expect most of them to cheat. Because the guy knows they can just get another girl anyway.
This is how I approach things. I have 3 or 4 needs that I must have met. These are really important to me. A girl I'm dating has to meet all 3 or 4 of my needs, before we get serious or have a chance of getting married. These criteria are "deal breakers". If I don't get these needs met, the relationship will have problems and probably fail. That also means, it's very hard for me to find that "perfect" girl. But I'm patient, and I know finding the right girls means success and happiness in the end.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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