My father wasn't exactly sure what day my birthday was on. For 30 years I thought my mother was born on the 25th, then found out it was the 26th. (She always wondered why I always gave her presents a day early.) My family always did something "in honor of "... "sometime around". We've even been known to reschedule Christmas. As a consequence, people who find celebrating a day ON the day of utmost importance is a real head scratcher to me. HOWEVER, I do know lots of those people. It doesn't matter that I don't get it, it's important to them, so I get with the program. I'm sure there are lots of things that are important to me that other people don't get. But the people who are my friends respect them.
Perhaps what this boils down to is that, just once, you'd like something to be important to him just because it's important to you. This is a milestone after all, and it doesn't seem like a lot to ask. Expect? Deserve? Out the window with 'em. It's what you want, along with a partner who will make a few concessions because of what you want. Those are standards and they are absolutely valid.