If you're aware of the mistake, and what you did wrong, you're now living with the knowledge on how to avoid making the same mistake in the future. You still exist in the here and now, and are free to continue forward in life, knowing you're better equipped to overcome adversity than you were before.

I try to think of my past mistakes as vaccines. They may have hurt, caused me discomfort, and even make me feel regret or shame to this day, but I lived through it and it made me stronger because of it. Like a vaccine, it equipped me for something more imposing that might come up later in life. It helps me think of the silver lining- that without these mistakes, I would be much more naive, and far more prone to making an even more disastrous mistake later in life, much like how refusing a vaccine will make you more prone to a deadly disease.

What doesn't kill you makes you stronger.