For how long have you known her, and from what situations? I don't know whether I can offer any good advice here, but I think that thinking about that question could perhaps clear things up a
little.
A lot of good points have been issued here. Personally, I would say that your first problem is not exactly the age difference. It's more the fact that you don't have a lot of friends, as you have stated. Be careful here.
Imagine you decide to pursue a relationship. If it works fine, then I think it'll be very sweet for you indeed. But if something goes wrong, whom do you have to turn to? From my personal experience I can tell you that a lack of friends (or only being unable to see them for a long while when you need them) can make failure in romantic matters much harder to bear. Also, personal unhapiness is not exactly a good starter. - Do not think about what she can give to you, but think about what you can give to her.
All that said, my advice would still be: Go for it if it feels right for you
