It is difficult to know what may be wrong. Visual hallucinations are experienced by individuals who have schizophrenia, schizoaffective disorder and on less frequent occasions, major depression and bipolar disorder, if there are psychotic features present. Approximately 16 to 72 percent of individuals with schizophrenic disorders have reported experiencing visual hallucinations. In that way, they can be relatively common among individuals who have those disorders.
Individuals can experience visual hallucinations in the absence of a psychotic disorder. In these cases, there may be an organic brain syndrome present. Some physical problems that may cause visual hallucinations include (but are not limited to): dementia, delirium, drug and alcohol withdrawal, severe sleep disturbances, migraine headaches, seizures or tumors. Generally it is recommended that an individual who is experiencing visual hallucinations be evaluated by both a psychiatrist and neurologist.
Your parents are unwilling to allow you to see a psychiatrist. I would encourage you to inform your parents that visual hallucinations are possibly a sign of a neurological problem. It is very important that you are medically evaluated to rule out the possibility of neurological problems. It would also be helpful to share this information with your therapist. He may be able to help convince your parents that you need to see a neurologist and or a psychiatrist. Please take care.