Jeremaih 17:9 The heart is deceitful above all things, and it is exceedingly corrupt: who can know it? The heart can be so deceitful God Himself said give me your heart and let your eyes observed my ways(proverbs 26:23). Maintain the hearts just like you maintain your phone or car. First, you will need a book, write down all the things God has done for you or all your favourite memory verses or all your favourite quotes and if for any reason you feel distress, discourage or disappointed. Go to your happy book and read them out loud and feel the difference P.s. protect your heart like a father protects his child.