In my religious past, I was conditioned to believe that everything was revealed or to be revealed. It took me years to diagnose how this belief had transferred to gave me an exaggerated view of what I had to reveal to other people.
Don't get me wrong, I believe in being honest (for the most part), but now for a sound reason... not a superstitious one.
As a humanist I relate it to survival. If we're never sure where we stand with people, then life gets to be so much more hard work. We need to be careful with our physical and emotional energy to aid survival.
I still have problems from time to time with how open I think I should be with people, and with how open I expect them to be with me.
But just as you can miss out because you are too 'closed', so you can go too far in the opposite direction.
I think it applies to every relationship in life. Once I realised what I was doing with my "openness" I could take a more adult approach to managing relationships.
Of course, if you feel you have to be "brutally" honest about yourself whether to a priest or a partner you can see how useful that is to them and how powerful it makes them.
In the case of partners perhaps not even a power they want.
Why wander into that minefield...?