Why I never go back--if at all possible

Yesterday, I drank a lot (more than a glass) for the first time in a long while.  I had to numb myself against the negative feelings about myself and my past.  My boss had scheduled a "get to know your boss's boss" mixer event that I had been dreading all week long.  If it was just an informal mixer, I would have just fake-smiled through the event.  But my boss had already told all the new hires to talk about oneself for 5 minutes each, and I knew he wanted us to talk about our personal aspects; and that was a problem because I know what my boss thinks about my past self: it's the shameful version of me that I am painfully aware of.  What made it worse is that both my boss and his boss are the "big men" that I had dreamed of becoming in my younger days.  Seeing (let alone talking to) my boss's boss always reopens my scar of regret.  During my turn at the 5 minute introduction, I tried to just talk about my current strengths (low level programming and system engineering), but as I feared, my boss jumped in and told other people about the distractions I dabbled in.  I know he doesn't do it out of malice; he thinks my past self is whimsically endearing--a positive trait, if you will.  So if I were the disgustingly positive person (you know, the people who are liberal with the exclamation mark, can communicate purely in emojis, and are the center of conversation and laughter around the water cooler), I could just suck it up, and play the part that is consistent with my boss's image of myself.

But I can't--at least not now--completely shake the regret about not having had the combination of personality and skills to climb the career ladder, and bitterness against the people who gave me hell about my shortcomings without recognizing my strengths.  I find that the bitterness against the malice of other people is easier to deal with if I justify it as an inherent human nature: it is what it is.

And why beholdest thou the mote that is in thy brother's eye, but considerest not the beam that is in thine own eye? 

Matthew 7:3-5

So for the most part, it is my own self that I cannot forgive.  Most people frame the wisdom of never go back in terms of the unchanging nature of the old problems in the other {place | person}, and I agree that people rarely change.  But at least in my case, going back to the old {place | relationship} where I experienced a failure just reopens my negative feelings about myself--which is not productive at all.  This is why I had turned down my boss's previous job offers several times, until he offered me a deeply embedded programming role, and I really wanted a secure employment for the next few years.

Being an introvert, I try to ride through the negative feelings by acknowledging my shortcomings and re-dedicating myself to my personal mission, and laughing through clenched teeth.  This coping mechanism has worked well for me in the past 6 years: I have never been more productive or happier in my life.  But I also understand why Google tries to hire fresh college graduates who don't have this kind of emotional baggage; the perfect employee if you will.  But when faced with a choice between two novels, one with a linear path to success (vendi, vidi, vici), and the other with a downfall and an ultimate redemption, I know which one I would reach for.