I don't know the whole story or background on the therapy work you've been doing, but my one question would be....would you feel better and manage better if you just quit this therapist?
Honestly, I relate to the feeling abandoned. I e-mail my therapist a lot when I'm in a crisis or melting down...sometimes a few times a day because she doesn't respond fast enough to the first one. I get really anxious when I'm in the thick of it. But she responds and when I think of it, that's amazing. Once in a while she lets me know she's busy with some other work, why she didn't respond right away....in a pretty gentle way she lets me know she has a lot of stuff beyond me that she's working with and I respect that she has her own boundaries. A lot of times I don't like it, but in a subtle way, I feel like this is also how she is teaching me about boundaries. Anyway, it's been challenging to stick through sometimes...
I had a response once that felt really hurtful and invalidating...it was on top of some pretty bad body feelings and nightmares, so I was going to be sensitive to any response. I curled into a ball and held my pocket knife all day...it was pretty horrid. I told her I wanted to quit, how I felt and how I imagined she felt. We talked about it a little at the next session. She apologized for her response and understood how I could have been hurt. She admitted she felt frustrated (by something I had done) and did not handle responding perfectly. I respected that. She's human and she can even be frustrated with me...but it helps A LOT that she never really lets me know this except for that one time...and it wasn't about "me" like I'm fundamentally f*cked up....she was frustrated with some things/behaviors.
It has also felt like the "rules", boundaries, or communication have been changing sometimes and I didn't know how to follow or respond (though overall she's very consistent)...I was just sure she was sick of me....totally afraid she'd give up on me in my worst moment. Ultimately that wasn't the case. But there was a period where things just felt very challenging. Anyway, I accepted her imperfect handling of the super hurtful response....it took time to feel more trust but I owed it to myself to not respond in my typical runaway fashion.
Not quitting through that was a good milestone. I would have been wrecked if I had quit and remembered the whole therapy with her by my final feelings of abandonment and rejection and everything that had built up. I hope you can at least meet with your therapist and let him know how hurt you were by the way he responded. I'm sorry you've been left feeling so deserted and I know how horrible that feels, especially when things aren't going well.
I don't know if this guy is the right therapist or not...I won't cast that judgment right now since I don't know your history much. But I hear it's hard and wonder if you can talk to him, even if you have to wait and sponge up all kinds of extra support elsewhere if needed until you can talk to him about all of this. ???