Everyone is with everyone in varying degrees in our situation. I know I can talk to E about most anything physical between him and T and him and me. With T, he's told me that he'll let me know if I'm telling him too much about things between E and me.
I second the idea of curiosity and perhaps hidden motives. However, the last thing you want is for your life to turn into Pandora's living room on Christmas morning. Never ask questions you don't really want to know the answers to.