Gay and bisexual people are most likely to be happy if they are able to express that side of their nature but right-wing Christians try and
brainwash persuade them into thinking their sexual orientations is some kind of abomination. Then the ex-gay movement says they can change you but you have to pay them vast amounts of money for the change that you don’t need. Sexual orientation can't be changed so people who believe this rubbish Scriptural message end off feeling inadequate when they fail. Now that can mean paying out more and more and more money to the wealthy ex-gay movement while trying to change and failing.
Later on gay men and women are encouraged to get into Heterosexual marriage and start Families to show they’ve changed. Temptation to follow their real sexual orientation re-emerges and all too often that means a broken marriage and a broken family.
Even the better Christians acknowledge that harm can happen.
I have seen that it is not a matter of bad people doing bad things to others in order to harm them. Rather too often we find good and sincere people acting naively, and as a result, unwittingly causing damage where they intended to bring blessing. 
Victims of ex-gay “therapy” can end off feeling uncomfortable with gay sex because of the conditioning they got from the destructive therapists, they also feel uncomfortable with Heterosexual sex because it’s not natural for them. So they end off with no good sexual expression. Parents reject gay Children because the ex-gay Christian movement tells them that their children are Sinful if they carry on being gay. Children are angry with their parents for because the ex-gay movement tells them their parents made them gay. More scientific Psychologists don’t think parents make their children gay.
- Gay exorcism
- George Alan Rekers He was actively promoting the Ex gay movement despite doing a vacation with a rent boy.
- The Ex-Gay Movement and Reparative Therapy
- Ideas for Recovery from Ex-Gay Harm
- Beyond Ex-Gay Harm
- Ex -Gay Therapy Is Scandalous Wayne Besen argues that argues that in some cases "Ex-gay therapy" amounts to gay sexual abuse.
- Stephen Fry meets an ex-gay therapist This therapist claims he can "cure" a third of his patients but can't show Stephen Fry any examples.
- Two Of Exodus' Founders Come Out As 'Ex-Ex-Gay' Two men trying to turn gay men straight fell in love with each other, well therapy wasn’t working. After they admitted they were gay loving Christians in their church treated them like dirt and one man’s sister even said she would pray that God would make him miserable for the rest of his life. There's more awful stuff in this video.
- Ex-Gay Therapy Stunted My Creative Growth This unfortunate young man was pressured into giving up the theatre and choir singing although he did both well. Afterall destructive therapists imagined that would stop him being gay.