The fact that he's 18 and you're 26 doesn't necessarily mean the relationship won't work.
The fact that he's hanging out in bars with a fake ID, asking you to buy him liquor, tacitly lied about his age, never dated before and generally acting like a college freshman is more the indicator of where he's at maturity-wise. And that's a deal-killer.
There's no easy way to do this but better to do it now than before you both dig the hole deeper. Just say, "We're in very different places in our life at the moment. You would be better off dating another guy who was in college and had more in common with you. We can be friends but we can't be more than that."
Couldn't of said that better.
Also, I love "Kiss From A Rose" and I'm 19. Knowing of popular classic rock songs do not make you mature or classy. It just means that you listen the radio. You know, where they still play songs made before 2000.
Age is a tricky debate when it comes to relationships and everyones view is different. Mostly what it comes down to is A. Emotional Maturity B. Stages of Commitment.
It doesn't matter if he is 18 or 54, if he acts like a stereotypical college fratboy, or an over dramatic sex fiend, it's probably a big turn off.
Age does not equal maturity, but it doesn't factor out of the equation either. While someone who is 50 might have more life experiences then someone who is 18, it doesn't mean that he is more mature than the 18 year old. Most commonly yes, he is more mature. Though the question is not how many life experiences you have had in your life, but how many lessons you have learned from your life experiences.
Stages of Commitment are a huge ordeal. Most of the time, an 18 year old and a 26 year old have different ideas of what they want in life at the time.
The 18 year old may be looking for fun random flings or casual dating while the 26 year old might be looking for something a bit more stable and long term.
Or the other way around. It fluctuates a lot. Basically if you can converse with your partner and make an understanding of your life goals, relationship, career etc, and coincide with each others, age will not be that large of a determining factor.
Though this guy seems like a total douchebag who just sees you as an opportunity to get crunk and fool around a bit. You don't need that. I'd say take Kara's advice.