My wife cooks every day and I never thank her. She says it does not bother her, but I notice she has gone quiet.

We both work, but she cooks almost every meal because I come home later. I always eat and say nothing. A few weeks ago I realised I have not said thank you in ages. When I asked her if something was wrong, she said "no" with a small smile. But she has stopped asking what I want to eat, and the dinners are quieter. I feel silly and guilty at the same time. I do not know whether to say sorry, take over some cooking, or both.