Mine has only done something like that a few times, in each event it was illness/injury. The first time was early on and I almost didn't go back. The second time was pretty devastating for me, I found out only an hour before my appointment and it was to be the first appointment after a 2 week vacation break.

The last time she cancelled on short notice, it wasn't too bad. She let me know it was an illness. I have lots of contact with her now so it's not as bad. I still get moments of panic where I'm afraid of a last minute cancellation.

Last week she brought up the possibility of needing to shuffle my appointments; that her schedule needed to flex by 15 mins. It was hard to deal with in the moment. It wasn't as intense as before but still hard. The ripples didn't last as long either - I was able to bounce back a bit faster. After I was calmer, I started wondering if the adjustment was so that her and the other T's in her building would have staggered start times to allow for in person sessions again. She didn't give any explanation and I think sometimes that makes it be harder.