There is absolutely no reason for consternation. The correct answer is simple and is exactly 4 words long: “Child, I love you.” And then, the parent should give the child a hug.
Absolutely nothing more is necessary - provided certain conditions are met. For the parent must always provide unconditional love to the child, no matter what the child says or does.
A child should know that he is loved unconditionally, that anything he does, says, or is will not shake his parents' love for him. He must know that although parents must disapprove of any evil actions he commits, he will never be rejected for anything he does or suffers.
This unconditional love is not acceptance of the consequences of the condition, of course. For love is far more than mere acceptance of flaws (something which many in the modern world are confused about). Parental love requires a willingness to demand the best of the child, to constantly seek the spiritual good of the child.
Parents should make clear to the child the meaning of marriage and sex – having “the talk,” if you will - BEFORE such issues arise. Thus, the child should know that temptations - such as homosexuality - are not sins, and can be overcome and turned into a greater good if borne patiently. The child should already know that his same-sex attraction is a cross that he can and must bear if he is to be a good Christian - and for that matter, a happy person.
This knowledge must be reinforced by the parents practicing a Christian lifestyle in their own marriage. Parents must make known to the child in their own lives the meaning of love – by embodying marital love in their dealings with their spouse; by lives of service and self sacrifice to one another
Is this problem difficult to resolve? Of course. But Christ demands that His followers take up their crosses if they are to follow Him.