“I told her I was fantasizing about her friend”

So this is the stupidest thing I have done yet…… a few days ago I got home from work, everything is fine, she was fine and I don’t know what came over me I decided to tell her that I had fantasized about one of her friends. With that said it changed the mood of the whole house. She stopped talking and being non responsive.

I know at that moment I messed up, I tried to explain at the time but it made things worse, I have never seen her this angry before. She has given me the silent treatment for 2 days now. I don’t know what to do. I don’t mind if people judge me for having those thoughts I know it’s a mistake and that because I am married I should only be faithful to my wife but I don’t even know if that counts as cheating. Do I wish I can take it all back? Of course, do I wish I never have those thoughts? Definitely. At the moment I am just waiting for her to forgive me but it feels like I am on death row. Please help?