I feel for you. It is never easy to know what might be helpful, but I will share my dad's experience, and if it doesn't help you, then forget it!
He actually asked to be alone that first Xmas. He had an invitation from a close friend for Xmas Eve, and he asked us not to phone. He spent the day in a mix of things he had loved to do with my mum, like a big fried breakfast, and things she wouldn't have done, like watching old films. He wrote down some Xmas memories, as the fancy took him, and went out for a Xmas walk.
He wanted to remember her in his own time, to cry when he wanted to, not be working to our timetable.
He then joined us for our regular Boxing Day outing.
It was the right thing to do, for him. I hope you can make your first lone Xmas one that helps you heal.