I would also find it impossible to work without contact between sessions, but I can understand your T withdrawing it if it seemed to be causing more damage than good. It doesn't mean his decision is necessarily the right/best one for you, but I think that's what he is trying to do. My T triggered me badly by withdrawing something he was doing (sitting with me on the floor). Tuesday, I had the benefit of hearing him describe to a support person he is introducing me to his whole impression of our treatment so far, including that episode. I really have confidence that he was just trying to do whatever he could to make our work more manageable. It didn't end up succeeding, but I know he was trying for my benefit. Eventually, the way we work got renegotiated, not because I pressured him to change it, but because I was (despite being terrified by his withdrawal) determined to be completely honest about my experience of the situation. I wanted to run, badly, in so many different ways, but I kept talking about it.
Obviously, communication and "keeping" your T outside of session is a real struggle for you. I think the outside communication probably WAS increasing the negative transference, but perhaps not the communication itself, but the way it was enacted. You might have had all sorts of invisible expectations about what sort of responses would soothe you in your need to reach out. When your T fell short of what was needed or simply could not provide it in his own time constraints, it left room for you to project your sense that you could not be valuable or worthy to him onto him. The only way I found to work through this issue was direct honesty:
-Being directly honest with T about what I needed (i.e. "I just need to know you're still there.").
-Being directly honest with T about what I feared (i.e. "I'm afraid you're mad," or "I'm afraid you don't believe me!").
-Being directly honest with myself about what I could reasonably expect from T (i.e. not to process huge amounts of information outside of sessions, but simply to "hear" me and, when he had a break, to let me know he was still there).
-Being directly honest with myself about where the negative thoughts about my T were coming from, that he hates me or is mad or wants to get rid of me, is all because either other people treated me that way or I have a deeply engrained sense of being worthless myself).
-Being directly honest with T when something he said or did triggered those messages, so we could discover its source together and I could distinguish between his intentions and my reception of him.
Anyway, it is ridiculously hard work and I don't think I could do it if my T wasn't willing to reassure me in between that he was still there. But, I think when it's creating a negative reaction, it can take a lot of work to find a method of reassurance that works for both of us (due to his schedule and my needs and my triggers). I honestly think, since this is such a sticking point for you, that you should keep talking about this need (that doesn't mean you need to demand he change things) until it feels resolved. If he is unwilling to hear everything that's coming up for you with it, take that in and continue to evaluate whether the course you guys are on is what is in your best interest...then I would be concerned. But, if he really seems to hear you, to want to understand your experience, to check in with himself what he believes will help you heal the most, then I would try to give things time to develop naturally. It was hard, but that's how things went with my T and we ended up with a really good relationship, despite the fact that both of us stuff up on the regular.
Anyway, I AM sorry this is so hard. I wish I knew a way to make it easier. But, as I tend to say, "the only way out is through." You can choose to stay "in" it if through is too painful, but "out" is much better, if you can make it.