Ripe, your list is really good. The PMA a s being polite is a must. You will not save anything this holiday, but a grumpy , rude h will leave a bad taste for sure.
Yes focus on your kids!!! No pressure on W for anything including physical affection or plans for when the trip is concluded. Listen and hear what she says.
Deep breath. Look good, smell great. Be witty. You will do wonderfully.
One note, you have not failed db. You have not chosen to be done so there is still hope, no matter how dark things appear right now. These things take time, time is on your side!