Holidays are the toughest time.
Especially for the newly separated.

The only thing I can say is you will survive it.
Moment by heart-wrenching moment, you will survive.

Your "kids" shouldn't say if you're not going, they're not going.
They're not 12 years old for Christ's sake!

I would ignore her birthday.
But then I'm kinda hard on walk-aways at times.

Nevertheless...you reap what you sow.
And the sooner LBSs start letting WASs reap it, the harder reality hits them and they have a chance then of realizing the ways in which they actually had it pretty damn good.

It is, of course, your call to make.