I would practice my assertiveness training in this case, and even the use of a little drama. I might say, so to the person who has a physically imbalanced brain chemicals, who did not ask for this imbalance, who has been in and out of the hospital their entire life, who is simply trying to live a productive life like anyone else, is trying to pursue a little happiness of their own, would you say these ignorant things to their face? I sincerely hope not.
Wow, that felt good just typing that out