This type of stigma is why so many people are worried about talking about their mental health. People can become afraid to seek help because of the shame and stigma around mental illness.
I encourage you to watch what you say regarding mental health, don't joke about it and please educate yourself.
Here's a tiny bit of a start
Bipolar disorder is not DID:
In DSM-5 (American Psychiatric Association 2013) dissociative identity disorder (DID) is described as a disruption of identity characterized by two or more distinct personality states or an experience of possession
Bipolar disorder is not Schizophrenia
Bipolar disorder is not BPD:
BPD means borderline personality disorder (which has nothing to do with Schizophrenia either)