Most Helpful Guy
Don't be so quick to judge on age difference; I'm staying anonymous to save being judged by people like the other anonymous poster and this is more directed to him, but I'm a 22 year old that is all-but dating a 17 year old. Want to wait a while to make sure we're sure; by the time we're together I'll be 23 and she'll be 18 (I turn 23 first though).
Sure; we're in different life stages. I can run rings around her at the present, just as I can run rings around myself at that age. But I can also offer advice, give her my experience to help her with any struggles, support her if she needs it, and I absolutely adore her and vice versa. There will be cases where an older guy is trying to take advantage of his younger counterpart, but that by no means says that it is the same for all. Some people think longer term, and that's where compatibility really matters. If it works out - are you going to care in 2, 3, 5, 10 years time? No.
It sounds to me however that this guy is a little immature. Getting jealous because you like an accent yet saying things like that that clearly bother you? Not cool.
My advice; tell him you aren't happy with him telling you things like that. Make it clear you don't want to know; his past is his past, you don't care for his past exploits no matter what they are; all that matters is the here and now for you.
Suggesting getting married to you while you're only 18 though, too? Be careful, please.