Does fine really mean fine?

He walks in the door it’s later than usual. She had tried to convince herself before he arrived that she wouldn’t be grouchy. As usual he walks in and just stands there. Not an ounce of happiness appears on his face.
"God that is annoying" she thinks to herself.
"What’s wrong?" She asked
"Nothing, I’m fine" he replied non convincingly
She is so bothered by his constant bad moods and really tired of being brought down herself. She is angered by the constant need to feel like she is walking on egg shells while he is home.
He takes his jacket off and hat and just tosses them into a chair by the coat rack. He goes to the fridge to get a beer. No conversation. The room remains silent.
She goes on with her work. Not bothering to look away from the computer screen.
"Well what did you do all day?" he said snidely
"Oh nothing" she tries to stay calm
"Is everything ok" he asked
"Oh everything is just FINE!!!!" she smiles