I always say "follow your heart" - I know it sounds trite - but the times I haven't - I've looked back in regret. You don't want to be doing that. Play it out and see where it goes.
If she's into you enough to go against some of her cultural "rules" and strong enough to stand up to her family for something she wants without resenting you - let her make that decision. Just be aware that it's an issue.
I went out with a guy twelve years younger than me. I was 34, he was 22. We had
exactly the same sense of humor - we were kind of like two sides of the same coin. Of course, we were at such different points in our lives, we ended up going our separate ways - but the love will always be there ( we say we'll get together and settle down when I'm 52 and he's 40).

Anyway - when you find someone you love - you can't just give up - or at least that's what I believe. Good luck.