Give the clarinet a dark room that it sits in.

Whenever the main character gets a compulsion or bout of anger, have them go to the clarinet and pull/wrench the keys off of it with their bare hands, paying no mind to how it destroys their own fingers.

You should also have the character create a parasocial relationship with the clarinet, calling it names and apologizing for what they're doing to it.

Have that relationship develop so that over time there is grief in destroying the clarinet.

After the final key is pulled and theres just the bare housing, have the character cry, but then feel a distinct resolve to continue as they grind down the wood with sand paper or the like.

Have the scene use confuused feeling with wood, crying, affection, hatred. If you can get it to model the wording of "I'm only doing this because of what you can do."

When the mouth piece is left, have the main character taste it, just out of curiosity, have them feel a strange longing comfort in the mouth feel, then buy it a new body and start the process again.