Bad experiences scar you for life.. and you tend to remember the negatives more than you should. Perhaps you learn not to trust so much, not to let yourself go so deep; because everything of the past that you went through is still ringing in your ears loud and clear.
You remember what to avoid.. what not to say or do. You build a wall, high enough. So you will be safe.
But what then, when someone climbs over so easily? Break through your defenses?
Do you give the benefit of the doubt? Learn to have faith; when little is left?
And.. when there is more involved, than just emotions; does that mean you are more insured? That it's safer?
Perhaps, would it mean that everything is okay?