Trivializing people's depression is rude.
Mary is sitting with John on the couch when she tells John that she is feeling very depressed lately.
John wants to respond to Mary.
John tells Mary that depression is a serious health issue that requires expert assistance and offers to help Mary find a therapist.
"John tells Mary that depression is easily cured by ""Simply cheering up"" and tells her not to look so glum."
Mary is depressed, so she can't be too happy but is momentarily relieved that John is going to try to help her get better.
Mary is devastated that John doesn't understand how deep and strong depression is and feels alone in her struggle.