Is there a way to get rid of despair and pessimism despite professional and academic success?

Your work to bring happiness and satisfaction to those around you, and your efforts to fulfill their needs, will be in the scale of your good deeds, for the Prophet, peace and blessings be upon him, said: "The most beloved of people to Allah are those who are most beneficial to people. And the most beloved of deeds to Allah, the Mighty and Exalted, is a joy that you bring to a Muslim, or relieving him of a hardship, or paying off a debt for him, or dispelling his hunger. And to walk with my Muslim brother to fulfill a need is more beloved to me than to seclude myself in the mosque for a month. And whoever restrains his anger, Allah will cover his shortcomings. And whoever suppresses his rage, even if he wishes to vent it, Allah will fill his heart with contentment on the Day of Judgment. And whoever walks with his Muslim brother for his need until he fulfills it for him, Allah will make his feet firm on the Day when feet will slip. And indeed, bad manners spoil deeds as vinegar spoils honey."

Your concern should be Allah's satisfaction with you, not people's satisfaction. For "Allah's satisfaction is commanded and achievable, while people's satisfaction is neither commanded nor achievable." Imam Al-Shafi'i said: "People's satisfaction is a goal that cannot be attained." If you satisfy Allah, He will be pleased with you and make people pleased with you. And if you satisfy people by displeasing Allah, Allah will be displeased with you and make people displeased with you.

Have good expectations of your Lord, be optimistic, and beware of despair and losing hope in Allah's mercy. For Allah Almighty said in a Hadith (definition) Qudsi: "I am as My servant thinks of Me."

Increase your knowledge of Allah and draw closer to Him by contemplating the Quran, seeking Islamic knowledge, attending religious gatherings, reading books, listening to Islamic tapes, and associating with righteous sisters, for their companionship is among the greatest causes of steadfastness. And never abandon supplication, for it is the essence and core of worship.