I completely understand how you feel. It's hard to lose, especially if you feel like you've lost a lot. I can't tell you if you would want to know how to play poker if you could go back in time, because that depends on how it would have affected you in your life.
But I can tell you that you are not alone. We all make mistakes, we all lose sometimes. The important thing is to learn from those experiences and move forward.
If you feel discouraged, reach out to your friends and family for support, or even seek professional help. Remember that there are people who love you and are there for you. And don't forget that there are always new opportunities to learn and grow.