What is the supplication or action by which a woman can remove perpetual fear and feel happiness, knowing that she is committed to her prayers and Sunnahs, but suffers from fear and a lack of happiness?

The cure for fear lies in relying on Allah and trusting Him, and in believing that everything that happens in the universe occurs by His decree and destiny. What is destined to befall a person could not have missed him, and what is destined to miss him could not have befallen him. This should be coupled with frequent recitation of the authentic supplications for the removal of worry and grief. True happiness is found in believing in Allah, being mindful of Him, frequently remembering Him, and being sincere to Him in word and deed.