> Learn from your friends, none of them have a relationship that will last. Horrible to say but it's true

This is partially true. Some people marry their highschool sweetheart and have a wonderful life together. These are the exception to the rule, though. Generally, teenagers are terrible at making decisions, including who they date and how they handle their relationships. Most people slowly learn from this process, which repeats itself in college (with the young adult addition of casual sex with that girl on the other side of your dorm) until people finally meet the person they spend the rest of their life with in the ages between 25 and 40. 

In short, don't worry about dating in high school. It's just a trial phase for most people and nothing life changing.