In the modern world, it's just critically important that you exert full control over your SO. You wouldn't want them to run off and leak your most intimate secrets to others without your knowledge or control. I'm sure a lot of us could tell stories about our SOs that we didn't fully control and how they ended up leaking a lot of critical information about us. So full control is definitely mandatory in any SO relationship. It's really just prudent
wait something's gone wrong here