Seriously, who does this?

So, as most of my regular readers know, it is once again that time when my MIL graces us with her presence. I was starting to think that maybe, just maybe her visit wouldn't be SO bad this year. Oh how wrong I was...
So apparently, two days before coming here, she was supposed to go to her dentist and have a crown fixed on her tooth. Her entire bottom bridge is being held together by super glue and one tooth and crown is gone completely. Instead of taking care of this, she didn't bother to show up for her dentist appointment and now, guess what? Her face is swollen and her tooth is infected. What a shock. And now, we are looking at emergency action, which my husband and I will be out of pocket for, to fix this. Sigh. It truly never ends.
I don't mind when "shit happens". I get it, that's life. What I don't like is when preventable shit happens that people just didn't take care of when they were supposed to, thus making it someone else's problem. Not ok. 13 days and counting.