It could be that he's feeling defensive (whether he has reason to or not) which is not to say you are making him feel that way, but that he's got his own hangups and insecurities and reacting to them. I know I use to be very defensive when my honesty was questioned, even though you don't know a more honest person :-) It took a long time before I could not take other people's perceptions and ideas about me as being about "Me" at all. "Your mother wears combat boots" doesn't bother 99.9% of people but there's that one whose mother does or did wear combat boots, etc. LOL

But, I agree with you, in a perfect world he should be supporting you and interested in talking with you and decreasing your fears and jumping through whatever reasonable hoops you requested to help you get over your dread of what the phone calls mean/were, and your suspicions, etc.

I wouldn't jump too fast though that he's necessarily guilty and that your feelings/hunches are 100% correct and/or that he's feeling guilty and thus responding because of that; but it looks like your T knows what's going on so I'd try and figure out which way to "jump" from that, whether the whole thing is worth battling through and if there's hope for him, etc.