MsQueen - Your feelings are totally valid and don't let anyone tell you they are not.
I totally appreciate the toll that your DC will be taking in your relationship. However, this is the very reason why you have to make an effort with each other (when I say "you", I mean him). In 10 years the DC will be gone and then what?
Buying you birthday and Xmas gifts is not a romantic gesture, it is a very basic life skill. It doesn't matter if he himself is not bothered about receiving gifts on such occasions - you are. If it matters to you, it should matter to him. Also he is setting a bad model to your DC. My DC get almost as excited on my birthday as on their own. They love to see me opening gifts. These moments are precious really.
My husband is an extreme workaholic and has his issues for sure. But - he has always said that just because we're married, it doesn't mean he can't take me on a date. He has always done this at least fortnightly - even if he had to drag me out the house when the DC were babies! He organises the babysitter too so I don't have an excuse not to
He isn't that bothered about gifts for himself either, but it doesn't stop him buying me things I love and organising our 4 DC to do the same. I don't get all the "oh it's a man thing". DH hates shops, but if he can buy me jewellery, lingerie or clothes that I like and that fit, then so can anyone. It's not that hard - go online if you have to.
Could you try writing to your DH. Tell him life is short and you need to celebrate the good bits, or what is the point? Maybe he doesn't fully appreciate how you feel. You need to tell him in no uncertain terms. Don't be afraid of making a fuss. When your birthday is coming up, you may have to pointedly and repeatedly ask him what he is planning etc, but do it and he will get the idea eventually.