People say "I learned it the hard way" when in the end they lost something for eternity, went through suffering etc. Like a recovered drug addict with permanent health damage or someone who turned on the path of crime and spent his youth behind bars or something. To me it seems like you had a pretty good life, took on some debt to live even more carelessly and then matured and calmed down and channeled more of your disposable income into paying back said debt. I don't see the hardship based on your comments so far.
you know there are gray scales in life, right? Things can be hard without somebody dying. Marriage is hard. Raising children is hard. Those things are hard without dying, drug addiction, or other exceptionally hard circumstances.
You mention some pretty heavy consequences to learn lessons.
I'd say committing to something for 3-4 years that means telling yourself NO is pretty hard. Its not "survive being a Vietnam Prisoner of War" hard, but I never claimed it was.
Actually, "learned it the hard way" refers to making the mistake yourself, rather than learning from someone else's mistake and avoiding making the mistake yourself at all.
It's better to learn from others mistakes, than to "learn it the hard way".
"The prudent sees danger and hides himself, but the simple go on and suffer for it." - Proverbs 22:3
