This being Easter, I feel this odd temptation to channel the inner angel.

Yes, this woman acted and spoke thoughtlessly. You can't know if she was trying to be a jerk, or just is just so caught in her own mind that she does not see beyond the end of her nose. You do, and it's wonderful, because it puts you in a unique situation. You can do something.

You already wrote here, and we can now reflect how easily we can be as thoughtless as our co-worker, rattling off about something, without any awareness or, as that co-worker, a reflection (she couldn't have escaped knowing, could she?) on the situation of our listeners.

Perhaps also you can think up a way you can express your understanding, empathy, support and admiration to your manager in the light of that co-worker thoughtlessness. It's may be not easy to do, because it is at work, and she is your manager, so how do you express your empathy without it appearing like you are trying to curry a favor with her or make yourself appear better than the thoughtless-acting co-worker, and all that stuff? Maybe there is no direct way, maybe only in the realm of spirit (whether you pray or not, there is plenty of indication that prayerful well-wishing intent has a positive effect on people, even when they are not informed)

Your indignation at your co-worker cushy arrangement for herself can also be seen as a challenge for you to not feel anger, or contempt, but find a measure of love, too. Can you imagine helping her to open her eyes and see the plight of the manager without delivering a judgment (not easy either).

And for what you've already done, thank you, and have a wonderful Easter.