another problem with words - dual diagnosis and complex needs

There is a problem with this terminology. Dual diagnosis was a diagnosis
I received and meant drug addictions and other mental illness. It is
also known as complex needs. Some people know both of these to mean
mental illness and a learning disability.

In my opinion Dual diagnosis means comordibity, i.e. a primary and a
secondary diagnosis, however the sense I am using it in in recent posts
is comorbidity of addictions and another mental illness.