Heterosexuality is often a name for this entire package, even though attachment to the other sex is only one element. If you deviate at any point from this program, you do so at your own cost. And one of the things straight culture hates most is a sign that the different parts of the package might be recombined in an infinite number of ways. But experience shows that this is just what tends to happen. If heterosexuality requires the entire sequence, then it is very fragile. No wonder it needs so much terror to induce compliance.