Hi blue_moon2
It's a "Catch-22". Why? Because, eventually a romantic relationship will lead to having sex, if you withhold and the guy really likes you, you may appear as cold or frigid. If you continue holding out long enough the guy who is genuinley interested in you may vanish without a trace. However, there maybe guys who are after a one night stand and are prepared to wait for it (For as long as it takes) and then dump you once they had it. So, at the end it all really comes down to the art of ancient skills, pciked up only with experience and time 
I know some girls who are virgin, avoid sex until marriage. And that sometimes works provided they find the right person (Similar culture, rationale etc...) However, I personally find that to be a Catch-22 as well. Because what if the person you end up marrying is terrible at it? You are forced to stay with that person when part of you will never be satisfyed.
Anyways, Just my 2 cents in the hat
Don't cry, don't regret and don't blame
Weak find the whip, willing find freedom
Towards the sun, carry your name
In warm hands you are given
Ask the wind for the way
Uncertainty's gone, your path will unravel
Accept all as it is and do not blame
God or the Devil
~Born to Live - Mavrik~