How to stop such bad thoughts from coming in and more importantly, how to keep faith in such scenarios?
Turn the mind away rather than trying to stop these thoughts. Even if they play in the background don’t give them attention or importance especially by acting upon them. If they try to invade either just step back and be a witness without judging them or do some physical activity such as arranging the cupboards. Read something from The Mother and Sri Aurobindo’s writings everyday and do Her Naam Japa inwardly in the heart. Take it like a wave that will pass away. The less attention and importance you give the sooner it will leave you.
Affectionately,
Alok Da