Like you say depends in certain situations. Ordinarily I don't see age being a huge hangup. Esp when both ppl are at least in their 20's (and above), younger than that there's a question of emotional maturity yet to be reached (some never mature regardless age! haha) and the potential of problems you might not necessarily get with age/experience (I refer to LIFE experience of course, not rooting around).
Look providing you're both of consenting age and no one's getting unduly hurt then what does age matter? You love each other, so be it, happy for you. Don't let people dictate because of their insecurities for whatever reason. My mother is 7 years older than my stepdad and they've been married 12 years now, they seem happy enough.
I have personal preferences though. I usually don't like younger guys, they're far too emotionally immature. On occasion I may be wrong, personally haven't seen it. I don't like guys over 10 years older. I start getting the daddy-complex. So I guess, as I said, it comes down to choice and of course socially exceptional standards (for instance, pre-teens and adults, teachers and students, doctors and patients, adults and elders - worked for Anna Nicole
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and so on). If you're head over heels for a guy but everyone in your life thinks its a bad idea due to age differences alone then you might be adding undue pressure on yourself and your budding relationship to stay with this person just because you want to prove everyone wrong. In such an instance if you really were in love there'd be no reason why he/she couldn't wait for you. One way to validate feelings I guess.
But you two are in college. Let's face it 6 years isn't a drama. In effect it may seem weird if
you were 6 years older (some people would think its weird, not me, but another social drama) - I think you may be over-thinking things. No sweat so far as I see or anyone else should. Like I said if you were 16 and he were in college I might start thinking it's a bit... unsavory. No matter. No biggie. Enjoy yourself
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Be good. Be SAFE. Have fun. No one said it has to be a forever thing... unless you want it to be.