It looks like you describing homosexuality as a birth generated mental condition/disorder. Do you?
It is, many, if not most homosexuals today are born homosexual. It's a condition they are born with, it's a broken condition, same as being born addicted to crack, born blind, born autistic, born schitzophrenic etc...
This is first of all, supported by research today, second of all, nothing is wrong with it as far as Orthodoxy is concerned. The problem is that you could call it a "mis-wiring" of the brain. Same with people who may be born as a man, but identify strongly as a woman. Or an outward physical condition being born as "intersex". It's an inherent brokenness in the person, whether its physical or psychological. It cannot be reversed, a homosexual cannot change and become a heterosexual, a man who identifies as a woman cannot become a man who identifies as a man (but he also cannot become a woman, despite any physical changes he makes), someone who is born intersex cannot magically become "normal".
What these people can do, is seek salvation despite their conditions. They can find unholy temptations, and they can seek repentance. But they cannot change their conditions they were born with.
Being attracted sexually to the same sex is different than being attracted sexually to the opposite sex. One may assert that there is no difference, based on the current social environment, but that doesn't mean it's what the Church teaches. It's a condition in opposition to the purpose for which we were created. Actually, the ideal is to be celibate and chaste and dedicate ourselves to God, body and mind. But as St. Paul says, if you cannot avoid fornication, it is better to marry. The problem for homosexuals is not that they are barred from being married by the Orthodox Church. The problem is their same sex orientation. That's not going to be mended by the Church being willing to marry them.
By describing a certain state of mind, inner disposition, attraction, etc. as sinful does not, by the way, equate with condemnation. Could it be that you are looking for a way not to condemn your friends by coming up with a rationale for homosexuality, rather coming to a proper understanding of what the Church teaches on the nature of sin. Sin is a diagnostic tool that the Church uses, not a condemnation.
In a sense, yes the problem is their sexual orientation. But that is something that is impossible to reverse. Homosexuals can't become heterosexuals and vice versa. It is a broken condition, but it is not a sin. Homosexual actions and activity is a sin, but having homosexual orientation is not a sin. Like I said, if it is, then Fr. Seraphim Rose was sinning even unto his last day, because he was a homosexual, and that didn't change even up to his death. Did he fight his temptations? Did he live a chaste, repentant life? Yes... But he didn't "reverse" his homosexuality and become heterosexual.