Those mess ups can be forgiven, rewoven/rethought as past mistakes....stupidity of youth.....carved into the brain in not such a black and white way. You can apologize if that is needed. When you lose something you feel is valuable or love, that is a true loss....and you will grieve. When you lose someone you weren't good enough for or who intentionally hurt you, you are only changing something for the better.....but change is hard.When you realize that you lost everything and you are going to be alone forever. You can’t live in the moment and you messed up so many things that you can’t fix. When your nightmares become your reality.
There is the sound of living by yourself. Stop......listen......you only hear your own criticism....no one elses. You can create your own drama...and likely will if that's what you are used to even...if you live alone. But you don't have to.....that's your choice. In living alone, you don't have to please anyone but yourself (maybe your pets), and you don't have to share if you aren't in the mood-you live alone. Quiet is a wondrous sound. Living alone and being alone are two different things. Some people feel like if they don't have family, they are alone.....but I have found people who love me, who treat me better than my family ever did, and they do what they say....walk their talk....mean what they say. I can trust them to follow through. It did require making new friends with similar interests.
So, I think resigning yourself to being alone forever.......really very bleak outcome that doesn't need to happen....unless that is the way you choose it to be.