I agree with you; It shouldn't happen in the first place. No one is disagreeing with that. But you still haven't answered the question, when it does happen, then what??
Islam strictly forbids extramarital, premarital, and homosexual relationships. These are also considered a major sins and should never be publicized. Even a lustful gaze is considered sinful. Parents are strict as well and try to be present but they cannot be present 100% of the time. So even with all the efforts, for whatever reason, people still give in to their desires. I'm sure you've sinned before in some form, because you're not perfect, so what did you do afterwards?
If they don't have regret, they will continue to accumulate sins and it may get worse and worse.
Unfortunately there is the risk that a vicious circle is created.
I repeat my question : why should a person expect marriage before having sex if God will forgives her/his sin?
A girl who wants to wait for marriage, reading and listening to such stories, could fall into temptation. She could ask herself "If God has forgiven my friends, He will also forgive me".
In this way Islam loses credibility, but God risks to lose his supremacy.
Take me, for example: many muslim people have told me that when a Catholic converts to Islam, it is as if he born again, all sins are erased.
Following this philosophy, then I could do this: have fun with all the possible girls..but even drink, smoke, drug. In short, enjoy my life in all its transgressions.
Afterwards, convert me to Islam and say "Hey, I'm a new person! I've become pure! That's because God forgives me!".
I dont think it will be correct: losing my virginity would be like taking away something that belongs to my wife, it would be my gift to tell her that she is so special to have waited so many years.
And then, some genius, has the courage to tell me that my intentions are corrupt or that I am a pervert.
Anyway, under the religious side I dont know what could be done, but under the moral / human profile yes: simply, dont hide/fix our past.
Dont look for subterfuges to return virgins physically or do "alternative things", dont pretend to be who we arent.
It is a marriage that can last even 50-60 years.
It would be enough to talk about it serenely, look in the eyes each other, and then decide "Yes, we are compatible" or "No, we are too different".
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Secondly freely talking to women about their chastity or sexual nature is absolutely forbidden as well. A girl who is open to talk to you in that manner will probably not be chaste even if she is a Muslim girl. So please keep that in mind.
Now I ask you a question: if you were a boy, how would you act?
You cant ask intimate questions, but at the same time you do not know if she is the right girl for you.
If all the Muslim girls followed the Islamic rules, what reason would I have to ask some questions? To ask about the sexual past would be stupid, useless, offensive. Because it's obvious that any girl had a boyfriend before. And what intrigues me are the married marriages: how is this topic treated between the two future spouses?
And in fact, when I read the Koran and Islamic traditions, I felt relieved: it would be enough to find a good Muslim girl (obviously a practicing) and finally I would find serenity and salvation.
But internet and Google showed me a very different reality. I've read stories that made me lose all certainty.