According to one report, the favorite, most-requested song in karaoke joints across Japan is Frank Sinatra's "My Way." One line of Japan's favorite sing-along-song is "Regrets, I've had a few, / but then again, too few to mention." That may be true for the crooner in question, but not, I daresay, for the average person. I think most of us can look back on life and, even if we agree things went as they ultimately should have, compile a list of regrets. Bad decisions, missed opportunities, things we wish we could do over. No matter how good we have it, regret lurks in the back of our minds and whispers dark things in our ears.
Why did I do that?
Wish I would've taken that other job.
I should've asked him/her out in high school.
I wish I would've taken more time for my family/myself.
I never should have gone to college.
Chances are, even if none of those fit your exact circumstances, they still speak to you on some level. It may not be your personal list of regrets, but they sound a lot like some of the things that do appear on your list.
It's easy to get stuck in the past and constantly review your mistakes. It's part of human nature to make ourselves feel bad, I think, to sometimes rub salt in our own wounds. Regret is great for that. Regret is the perfect way to refuse to heal, to peel the scabs off and start the bleeding anew. Regret will always find ways to let us kick ourselves while we're down and drive us to the Job-esque point of wishing we had never been born (Job 3:1-12).
And that's just not good.
For starters, it's futile to want to change the past. The past is fixed, incapable of being altered in any way. People have gone crazy lamenting that fact and wishing it otherwise, but it will never work any other way. Moreover, God has a future for you, one that won't fill you with regret. But you have to leave the past behind to find it.
Don't regret the past. Learn from it. Then follow God into a glorious future.