To worry anxiously or be despondent about something or someone, especially at great length and in isolation. I know you're upset about failing your exam, but don't brood over it all weekend.Tom's been brooding over our financial situation ever since he got laid off last month.
and brood on someone or something; brood over someone or something
to fret or be depressed about someone or something. Please don't brood about Albert. He is no good for you.There's no need to brood on Jeff. He can take care of himself.