I'll have to be social, fake and happy all day.
Excuse me, but Um NO, no you don't. You don't want to celebrate? Don't tell him flat out, you are not going to celebrate, you will not be attending, and you want NO ONE to acknowledge it, and if that means you spend the day hiding under a rock you do it.
My point is, you get to decide this stuff. A really remorseful spouse will do whatever it takes to get through this stuff. He can get annoyed by you not wanting to celebrate, but he better damn well respect your wishes.
The year H was having his A, he forgot our anniversary, or was so wrapped up in guilt that he couldn't in good conscience celebrate. He did get me a card last minute, and just signed his name, no hand written sentiment, nothing, just his name, and the kicker, it was in pencil. WTF?
I was so blown away by it I couldn't believe he was so fing heartless. The next anniversary we were well on our way to R. Did I want to celebrate it? No. My biggest fear was that he would forget again though. So I warned him I wanted something, some sort of realization that it was a special day. He didn't let me down, he got my parents to watch the kids and took me fishing for 3 days. Just us. Alone, on a lake, it was perfect. We talked about whatever we wanted, and yes that included talk of the A. We have done it every year since.
I will be damned if that day is ruined for me because he was an ass. Nope that is a good day and a great memory for me. When we got Married it was really a thing that I had worked hard for so we could get married. It meant I had achieved some pretty high goals I had set for myself. I still celebrate it.