I'm not going to tell you what to do, but here's what I'd do:
I'd invite a bunch of my friends over for holiday drinks/meal/whatever. That way, I'd be forced to decorate a little, but I would be thinking about my guests coming while doing so, rather then lamenting that my daughter won't be there to see the decorations.
When your friends ask how you're doing, and they likely will, considering your family situation, tell them the truth without making a huge deal. "It's tough not having my daughter around, but I'm hoping to surround myself with friends to get me through the holidays". This way you don't sound pathetic, and your friends will empathize with your situation. This could garner some great invitations to events that will further keep your mind off the pain that you're feeling.
I've been there, it sucks.