What is up with no questions asked in a relationship?

Every time I ask a question I get the defense. I don't understand what is up with that. He says its because his ex-wife used to grill him and questioned his every move. I'm not her and I have told him that. It makes me so mad and bitter toward him every time I in general ask something as simple as "What did you have for lunch today?" and I get "Why?". I feel like I'm like I have to guard everything I say so that it doesn't come out as a question. I'm so furious about it.