Very sorry to hear that
, I would urge you to take a week break and think about it. I do not think there is a delete key, so not logging in is perhaps the only way I know to stop playing. It may be worth putting players up for sale before you do just in case there's a gem or two in there that could slip through the free agent net - I see you have a NT player for Indonesia at the moment and I am sure they would appreciate the sale before free agency to keep gameshape.
Would be sorry to lose a good manager.