It sounds to me like you're saying that some people get involved in the personal lives of others with the hopes of helping them make what they believe are the right decisions. This is very similar to the attitude of religious folk who make it their business to proselytize, who often have good intentions and hope to save the souls of others. However, while they may mean well, proselytizing can be "considered inappropriate, disrespectful, and offensive by some individuals." This is for a number of reasons, such as simply varying opinions and views about religion and god. The same thing applies to sex. We're each allowed to have differing, unique views about it, such as the significance of it, when to have it and who to have it with. If one person believes that sex before marriage is a disgusting, sinful act, then they simply don't have to have sex before marriage. They may have the best of intentions when they try to make others believe the same thing, but that doesn't mean their actions will be well-received, never mind being effective.
And fair enough, I just figured I'd ask since we cleared up the miscommunication. :>