Regardless if he is busy or not I think you need to let him know how you are feeling.
He most likely isn't going to remember because he wants to forget the pain and hurt it caused.
For the first year every month on the 16th (DDay) I would tell my husband this is going to be a really hard day for me.
The one year anniversary, I told him although I am in a good place I really hate this day.
My husband responded that he was sorry, thanked me for standing by him and gave me a huge hug.
Embrace your feelings because they matter.
Simply say "It's been a year today. I am proud of how far we have come but it is still a hard day for me"
Good luck and I am so glad you are in a good place.