When our lives become as difficult as this, we have mental health problems. They can be mild or severe - some get better quickly but sometimes they last a long time and people need a lot of help. The term 'mental illness' refers to the extreme end of these difficulties when some people, at different times of their lives, become so confused and out of touch with reality that they can barely cope with everyday living. We can all see if someone has a broken leg, but it's not so easy to tell if someone is mentally ill. And because some symptoms might upset or frighten you, it can be hard to feel nice or kind to someone with a mental illness.
Psychosis is a serious mental illness.
The most common forms of psychotic illness are 'schizophrenia' and 'bi-polar affective disorder'. A lot of people who have schizophrenia hear voices which no-one else can hear. They might also talk back to these voices. Having schizophrenia can make people lose interest in everyday living and make it hard for them to talk or show affection or even to eat or dress properly. People who have bi-polar affective disorder suffer from extreme changes of mood.