Here's what I have observed based on my experience, it is more the person's attitude toward sex. If you believe sex is to stay in the confines of a marriage, you (or your partner) are less likely to cheat once married. Now this is not a hard and fast rule, as people who waited until marriage cheat on their spouse and people who had multiple partners do not. But in my experience, or maybe just with my group of friend, those that waited until marriage are still married today 15-20 years later and those that didn't, especially if they cohabitated, one or both cheated and ended in divorce.

I am going to assume you are young and you are going to find that most guys in their early to mid 20's are just looking to get laid. That is actually pretty normal (again, not all, but most), so sex is going to be important to them in any relationship they have. As they get older and more serious about settling down, it is less an issue because they are looking for other qualities in a mate. I waited until I was married (age 27) and experienced the same thing you talk about in my early 20's. I just chalked it up to "guy didn't really like me so why would I give it up to him anyway". It was frustrating at times, but to me worth the wait. I have a great sex life 15 years later. It was a little bumpy in the beginning but that was just due to inexperience on my part. I didn't have any hang ups regarding sex and it all worked out in short time. My hubs says he got to mold me just how he likes it.

Also, my hubs and I have a high level of trust in our relationship. This is due to having the same attitudes toward sex - it should be in a marriage. He wasn't a virgin when we married but had no problem with my values. When you find the guy that is right for you, he may not be happy about not having sex, but it won't be a deal breaker.