I find it hard to maintain eye contact even though I'm one of the rare beasts who can do public speaking. Up on a podium, talking about war or cultures or religion? No problem.
Talking about me and my past? Nope.
I feel like if I don't make eye contact it buffers me from what I'm saying. If I make eye contact I'm more likely to burst into tears and I still have that trauma induced of "don't you dare!" paired with "stop bawling you're just being overdramatic!" (how one is overdramatic about being kicked down a flight of stairs, who knows, but abusers aren't always that sane themselves)
As recoveringfromptsd stated, I think most of us have eye contact problems, it's a way we either protect ourselves or try to numb the hurt and pain that comes with therapy. I'm sure your T knows about it and is familiar with the phenomenon.