Desensitized

Dear internet,I’m searching for the word for how when you walk into a room and there’s a bad smell and then a few minutes later you don’t smell it any more. For how you become acclimated to certain sensations so they no longer register in your consciousness. Because I am worried about the emotional equivalent to that. Happiness shouldn’t be so transient, right? And for grief to gradually wane seems like a betrayal.