(((hangingon))),
I am SO sorry this is happening to you!
I agree with everyone. I've seen my T for 6 years and she never cancelled a session! Maybe a couple of times she called me to change the time or date. That's all. She knows consistency is very important to me.
I thought of one explanation that could explain your T's behavior but it doesn't excuse it. She said she was taking personal leave, not vacation. That rang a bell for me. Could it be that she or someone close to her is ill, or that there is some serious problem in her personal life? Something major may be going on, or why would she take "personal leave" and not call it vacation? Maybe she will be so preoccupied that she won't be able to read emails.
Of course a T's personal life should be separate from her professional work of being a competent T. It just seems like something is going on with her, and she is letting it interfere with her work. It's not your fault at all! I don't know if you should go back or not unless you can settle this with her. Maybe it's best to find someone else.