He goes quiet again for a moment or two, thinking. Does she? He'd thought the answer would come immediately, the way everything that he knows without having to consider it does, but now that he does consider it...

"I'm not sure," he says slowly. "It's not like... I mean, it's not like I've been hiding it or anything." Not on purpose. "But I don't know if I actually ever said anything about you. I think she knows I live with someone."

Questions about his body, his diet, his activity level and his sleeping patterns--and how much he fucking hates every second with her--these are all regular topics of conversation where Donna is concerned. But other things... Yes, but not in detail.

He's not sure how to even talk about those things with someone he hasn't already let in beyond that point. He's not sure what the words are, what vocabulary is involved.