I'm not sure how much of it is just terminology and how much is an actual difference, but I've found that many (unmarried) couples are still considered "dating"

I'm not sure how much of it is just terminology and how much is an actual difference, but I've found that many (unmarried) couples are still considered "dating" after a few years, whereas here in Europe (e.g. Germany) you would just be considered "a couple" or "together". In my relationship, I only went on a couple of "date" dates in the very beginning. I wouldn't say I'm "dating" my girlfriend although we do occasionally do classical couple activities like going for a nice dinner etc..