The following is a freely-translated excerpt from a letter by the Rebbe dated 24 Adar II, 5711 (March 8, 1951).
... I was extremely happy to read that you are working with your artistic talents, are preparing to hold an exhibition, and that you have already received favorable reviews in the press. Surely you will progress in the utilization of the talent that G-d has granted you toward the strengthening of Yiddishkeit and G-d-fearing behavior.
As to the main point of your letter, in which you complain about your circumstances, your depression, your despair, etc., and express the wish that we should meet, so that we could discuss the matter face to face.
For two good friends to get together is always a positive thing and a spiritual pleasure for them both. But to put off [the resolution of your problem] until then, and in the meantime to remain in a state of despair, G-d forbid—who can allow himself such a thing?
You do not write of the causes which bring you to this state of mind, so I cannot go into their details to show you how these “causes” are but imaginary and stem from the evil inclination—that is, that even if there is some substance to them, the fact that they lead to despair and depression is folly...
I must therefore confine myself to a general comment with which I hope to illuminate your particular situation. My comment is based on the saying by the Baal Shem Tov—which my father-in-law, the Rebbe, would often repeat—that a person can derive a lesson in the service of G-d from everything he sees or hears about.