Long Distance. Good or Bad.?

People tend to tell me "long distance is never good, they always end". But I seem to find that not true.
I've been in a long distance relationship for about 8 months now. I live in California and he lives in Texas. I'm 19 and hes 17 but wait he'll be 18 this nov. Even tho we are young and very far away some how we've already told each other how we wanna get married and everything. Me being how I am, not wanting to get hurt again but then holding back at the same time. Alot of people may say that "were too young to be thinking/talking like that" but I seem to disagree. Idkk :/ I see it as I'm happy for once, why go off and ruin it for me.