The introduction to the translation of Meditations that I read (by Gregory Hays) notes that it is fundamentally a book about how to defend against pain, not a way to find joy.
Marcus does not offer us a means of achieving happiness, but only a means of resisting pain.
Meditations, Kindle location 612
It’s worthwhile for you to look at this. You are what you eat, so to speak.
Just as you have deliberately turned to classical music and away from the routine music you listened to before, maybe it’s time to read books that create joy. Focus on offense rather than defense: create happiness rather than defend against sadness.
It’s just a thought.