Personally, I paid for all our entertainment and food whenever we went out. I bought here a $100 necklace the summer before I proposed (I already knew I was going to, was just waiting to get a ring and other things in line first) On birthdays, Christmas, and valentines day I would spend $30-50 on her.
Of course, I would keep the spending in check, and we would do lots of stuff for free or cheap.
So overall I would say I spent more than enough, but wouldn't classify it as anyone taking advantage of me or anything.