Didn't realize you were 16. Welcome to the "School of Relationship Hard Knocks"! I graduated summa CUM laude!
First off, I agree with the others...slow the alcohol consumption WAAAY down! You'll be paying for your own health care soon enough, and liver complications will keep you from making payments on your SLR!
If the girl is truly joining the Navy, then all she wanted was a casual evening out in the first place. A lot of guys don't take that well, so the "let's just be friends" line is usually the best way out...don't take it personally.
As far as being a nice guy? Don't hate yourself for that. While girls mature faster than guys, their tastes for men are pretty ridiculous at that age. Popularity and rebelliousness score points, so mostly jerks get the hotties.
When the biological clock goes from a tick to a BONG, girls are more sensible in their choice of a suitable mate.
Life has a way of putting things right with time.
I was the proverbial geeky, acne-infested nerd boy that couldn't buy a date in high school and college. But years later, I ended up marrying the hottie who was the cheerleader/athlete in high school and the sorority girl in college!
For now, I suggest casual dating, and expect no more than that, so that you won't set yourself for another disappointment.