Yes, gambling is a drug like any other (it's fun--but can be dangerous if overdone).
It's all about comfort level. If you're sweating out games and can't go for five minutes without thinking about what the score is (who hasn't been there?), you probably need to pull back and bet less.
I understand what people here are saying about the adrenline rush, but that only means you're betting too much. And when you go on that serious losing streak you'll probably consider killing yourself. So much for the rush.
The key is to bet enough to care, but not too much. Sounds simple, but surprisingly it's not.