Courage, I can relate a little. My husband didn't care at all about getting wedding and engagement rings. Nor did he care about a wedding. He's pretty much like you in that anything ceremonial just wasn't important to him. We eloped to make things simple, but I really wanted the rings. They were very important to me. So, we got the rings. And for a while my feelings were hurt because he didn't care at all about them.
Somehow I've just gotten over it all
We have crazy new problems new to supplant those, lol.
Maybe your son will, in time, be ok with how you feel