As Sam Kinison said - "You basically got to make an appointment for that folks, it doesn't just !@#%en happen"
Of course if a person becomes “addicted” to homosexual behavior (ie build strong neural associations between dopamine release and sexual encounters with the same sex) the person will be inextricably attracted to the same sex. However, these associations can only be solidified with stimulation (active engagement.)
In the end anyone who wants to leave homosexuality can, the same way as anyone who wants to remain faithful to their girlfriend or wife can.