To OP,

While I've not exactly had your experience I can sympathize with you and understand where you are coming from completely. My T is very good at giving me warning when he will be away and we do planning for it. If something comes up urgently and he has to cancel last minute he leaves the door open for emails. He's been very good over 4 years at not showing how he's doing in life in sessions but is still able to show emotional reactions to things I feel or have dealt with. However there was a time I had a therapist that was not so good at self care and keeping her stuff out of our sessions. I tried to ask her if something was wrong things felt off and when she would say no I would blame myself. Never any nail picking or anything (which is horrible by the way) but she wouldn't pick up on things very much wouldn't ask the extra questions to get the whole story and stuff. Eventually our therapy ended due to me moving and finding another therapist but it was rocky for a bit. Looking back I feel like had I brought it up in a way to say that I feel like it's my fault when you are distant and different then usual and it's affecting me negatively that she would have probably changed that behavior or something and maybe I would've felt more inclined to keep her as my therapist when I moved but that never happened.

All I can suggest is if the behavior continues to try to voice your feelings in a nice respectful way. Sure sometimes Ts have bad days and while I don't think cancelling is necessarily a good thing unless they can rebook soon (it really depends on the client and where they're at) I do think that advising the client they are having an off day and it's not their fault is an option then it's up to the client to keep the appointment or reschedule based on their preference maybe.

Anyway sorry I don't have much advice. I just wanted you to know I understood where you're coming from and feel you have very valid points and I don't think it's your fault at all and she should have made that clear to you not just to your husband.

Good luck and I hope you can find some peace with this and make the best choice FOR YOU. Best of luck.