There's such a thing as drug intervention programs where a friend or family member presumes to know what's best for the drug-addicted. And, of course, they actually do. And ray_afraid, if your smoking friend was diagnosed with lung cancer, wouldn't you make some sort of move if they continued smoking?
If there's a point I'm trying to make with my curiosity, it's that disagreement with but embracing of homosexuals is an exercise is complete and utter meaninglessness. Unless you kidnap your homosexual friend and send them to rehabilitation out of love, or frequently dissuade them from homosexuality, your beliefs against homosexuality amount to less than nothing.
You should drop the charade and be pro-homosexual. Help the world move forward.