You know, sometimes you just don't know

It can really become a problem if you aren't careful, the not
knowing. All is usually quite well in Blisstown, the realm of
ignorance, protected from what we don't know about those we care
about, those we tolerate, those we restrain ourselves with nearly
super-human strength from grabbing by the neck and .... Those are the
easiest to deal with, the ones we despise; you rarely learn anything
new that causes pain. Surprise, maybe, when you learn that some
shotbag that you wish you never met once did something honest or
slightly ethical, but one kitten not kicked does not a sympathetic
character make, it just doesn't work that way. Those folks you
tolerate, the ones that reel you closer with reasonable behavior,
those can be very trying, but as long as you keep in mind that they
have given you reason to keep them at a distance things usually work
out all right. Ahhh, but those other ones, those you care about, the
ones you expect the best from, no matter how many times they've let
you down, those people, harumph! Is the revelation that someone you
care about has let you down yet again the worst of it? No, at some
point that becomes the long-awaited relief. It's the pointless,
you-wouldn't-dare-screw-me-over-again-would-you, hope-against-hope
that is the worst of it. When someone always let's you down, that
predicatability can be a comfort, as long as you're willing to let it
be. Pretending, telling yourself that it isn't going to happen again,
that's harmful behavior. Besides, the immense joy of being surprised
by someone that you know better than to believe in is probably all the
greater once you have completely given up all hope.