Drugs.

Drug taking is tolerated mostly amongst rich celebrities, yet for people living outside the scope of celebrity while still taking drugs, the affect ruins lives according to a government report. Dealing with users paranoia can put a strain on family relationships. Mood swings and personality changes also affect relationships between partners of those using drugs. Drug use can cause users to loose control of their behaviour and things held of importance such as relationships, jobs, families and careers come second best to the drug itself. Drug use can account for mental illness causation.
Drugs associated as factors are: Cannabis, LSD, Heroin

Link to government website http:// www.parliament.uk/post/pn079.pdf