the only reason why being gay was removed from the list of psychiatric disorders is because of the number of gay people who went into psychology looking for answers on there own mental illness that were gay who then decided at a meeting of psychiatrist to reclassify themselves as healthy mentally.
There are numerous accounts of this, but I think in general the gay lobby forced Homsexuality from being listed as a mental disorder.
Please see: http://www.behaviorismandmentalhealth.com/2011/10/08/homosexuality-the-mental-illness-that-went-away/