Do relationships last over the summer?

There's this guy that I really like and during the school year I've felt like he's liked me back but...he started dating someone else. I think they're still dating, but me and the guy are still friends but it sucks because I really like him and we get along perfectly. I hate being so conceited but...do relationships usually last over the summer? I never thought they did but what do you guys think? And yes, i know i'm being awfully mean, secretly hoping they won't last :/ but we're all human, right?