Does your grief feel like you are drowning? When the Titanic started to go down people in the life boats had to row away from the ship. The energy of the ship created a vacuum and pulled everything down with it.
Negative thoughts can behave the same way; you have to get away from them, or they will pull you down.
“In the multitude of my thoughts within me thy comforts delight my soul.” Psalm 94:19