Since we are in the midst of the holiday season this article seemed particularly on point. I really liked the message that it is okay to say no and that you have that power and that right.
"How to Say 'No' to Holiday Season Invitations"
The day the Bump died - Jasper is wise

Re: How to Say 'No' to Holiday Invitations - Still Standing Article
You are less than a month out from your loss and to expect you to "keep on truckin" so you can throw a holiday party is selfish. If there is zero chance of cancelling the party, make sure you plan an "out" for those times when it gets to be too stressful. That's fine if he wants to pretend everything is okay, but you don't have to. If you need to step away and go have some quiet time in your bedroom or someone where else, he needs to support that and be prepared for it.
The day the Bump died - Jasper is wise
The day the Bump died - Jasper is wise