When it comes to relationships you have to have the mindset of what is going to be best for you overall. Relationships are about commitment, trust, lust, and friendship. If a relationship isn't working out and isn't worth staying/fighting for then your best bet is to leave before things get really bad. If you only care about what's happening now then stay single and hook up with people.
I'll be seventeen in two months, I've been single for over a year, and I couldn't care less. Of course, I've had "things" with plenty of girls and hook-ups, but not one girlfriend. And I'm sure almost all of you have probably heard this from a million different people but it's extremely true, if you're a teen then there's so many things in your life that are more important than a girlfriend.