What does the woman mean?

M: The teacher called me in the morning and said that Bob failed the English examination again. Do you think we should urge Bob to study English?
W: Bob is not interested in learning English. We’ll have to leave that decision up to him.

M: I thought you were going to call me last night. I was waiting the whole night.
W: I had intended to. But it was 12 o’clock when I got back home after meeting my friends. I didn’t want to disturb you.