Have you asked yourself why your parents are urging you not to go down the same path your friends are taking? It isn't because they're old-fashioned or don't understand the temptations you face -- because they do.
Instead, I suspect they're encouraging you to resist these temptations because they know the dangers you'll face if you give in to them. Some of them are physical; almost every day I get a letter or e-mail from someone who unexpectedly became pregnant, or contracted a sexually transmitted disease that will be with them the rest of their life. They never thought it would happen to them -- but it did.
But the dangers also are emotional and spiritual. God gave sex to us -- and one reason is so we could express our lasting love and commitment to our husband or wife. That's one reason why God commanded us to abstain from sex with anyone other than our spouse. But when we treat sex casually, we destroy its true meaning. Don't let this happen to you.
The most important thing I can tell you, however, is that God loves you, and He wants to come into your life and put your feet on the right path -- His path. By faith commit your life to Jesus Christ. Then ask Him to help you live for Him, no matter what others are doing. The Bible says, "Therefore glorify God in your body, and in your spirit, which are God's" (1 Corinthians 6:20, KJV).