It is just gone for some time. Patanjali yogins maintain that thought causes sorrow. There is definitely some truth to that. Their solution is to remove the thoughts. This is only a temporary solution since thought always come back.
Nobody permanently removes all thoughts and continues to live, except in a comatose condition.
If sorrow is caused by a thought build-up, the sorrow may be able to be destroyed by examining the validity of the thoughts. Psychotherapy does this to some degree. Vedanta goes one better by maintaining that the thoughts, whatever they are, are not as real as the Self. The sorrow causing thought is just a form like the clay pot is one of many forms clay can take. Mind is only eliminated when its relative nature is understood and the real nature of the Atma, the Self, is clear.