Thanks, Trisia, for the clear explanation.Hi again.
I meant this: what exactly does the sentence mean?
She was incredulous when her husband told her he wanted a divorce = He told her he wanted a divorce, and she didn't really believe that. She didn't suspect him of anything. "Doubtful" might work but it's a stretch.
Now I would only use suspicious or doubtful if you had something like "He told her he had been out with the boys but the was still suspicious/she doubted that."
EDIT: I see Loob's got some older threads. Nice!