When the only thing that keeps your marriage together is the church and the only thing that keeps you from liking the same sex is god, you keep on fighting.
Even if you don't fall into that category, one of the main gotchas of the church is to use one of your most basic biological programmings and tell you it's a sin. The church teaches that even thinking lustfully about someone is a sin. They tell you that the urge to reproduce is sinful and only they have the cure.