I agree, we all have our crosses to bear. Migraines are truly one of mine.
I don't think my migraines are about learning to accept pain since they're hereditary in my family: parents & my sister. My son started having migraines when he was about 8 years old.
For me personally, if there is a lesson in them at all it's 'Patience'.
Thankfully, Now that middle-age has hit, I still have headaches, but my headaches aren't as severe. Although on occasion, I still get a severe one.

I understand what your saying. Thank you for sharing more ideas for me to speculate on.