I have a new broken record that I’m playing as appropriate. Let’s start with a different assumption—that we exist as we do to taste of experience. Not that we grow and refine taste over time, but that we come into being to this end. I don’t prefer the word, karma, but it is a good enough placeholder. So, perhaps, we are not learning from pain so much as soaking up as much of it as is needed to fulfill a desire.
Pain also is only present so long as it has our attention. If forgotten, it may as well not exist. If the pain you speak of is so real and primary, how is it possible to forget and have disappear? If it is so pliable, is it really real? Or is it dependent upon our energy and attention?
Further, is it you who is pained, or is there a you that observes the pain? (Sit with this question and feel for the answer without too much thinking.) if your situation is the latter, then what is the disposition of the observer? (Answer for yourself.)
If there is an observer, is there anything that can cause the observer pain?
to answer your last question, it taught me that “reality” is reallly wobbly and led me to that which isn’t.