How can one overcome despair and pessimism after the death of a brother, and surmount the fear of death and the grave, while restoring the desire to live and complete one's studies, especially given that the questioner is religiously committed?

It is advised to fear Allah and to be patient in the face of trials, citing His Almighty's saying: {And give good tidings to the patient, Who, when adversity strikes them, say, "Indeed we belong to Allah, and indeed to Him we will return." Those are the ones upon whom are blessings from their Lord and mercy. And it is those who are the [rightly] guided.} [Al-Baqarah: 155-157], and His saying: {And whoever believes in Allah - He will guide his heart.} [At-Taghabun: 11]. This life is a house of trial, and a believer must be patient and entrust his affair to Allah, for all his affairs are good, as in the Hadith (definition): "Wondrous is the affair of the believer, for there is nothing in his affair but good; and this is not the case with anyone but the believer. If prosperity overtakes him, he thanks Allah, and that is good for him. And if adversity overtakes him, he endures patiently, and that is good for him." Contentment with divine decree brings tranquility to the heart and wards off the whispers of Satan. One must beware of despair, pessimism, and aversion to life, for these are among the whispers of Satan. Maintaining prayer and reciting the Quran is a sign of much good, and it is advised to associate with righteous women to renew and strengthen one's faith.