Exactly. The mental illness involves more than just making them look upon people of the same gender as sex objects—it permeates every aspect of their lives. Homosexuals who achieve a stable relationship and lifestyle analogous to a heterosexual lifestyle are, I believe, exceedingly rare—especially if they are men.
They are exceedingly rare. A recent study that caused a lot of stir was from the University of Texas (I think) that looked at parenting results of straight vs. gay. The preface of the study noted how very difficult is was to find gay couples that stayed together long enough to be comparable to a straight couple in raising children.