Many years ago I was offered a job, I took it, then completely messed up. My boss worked in another city so basically I was on my own. It was my first 'real' job after University and the real reason for taking it was to please my parents.
I was extremely uncomfortable, both during my induction day with my boss, and afterwards in my office. I ended up spending my days, alone in an office, watching the minutes crawl by, unsure of what I should be doing.
I lacked confidence, had no self-esteem, and rather than explain any issues to my boss, I retreated further and further into myself and eventually just stopped showing up at work.
I eventually worked up the courage a few weeks later to call my boss and tell him that I was no longer going into work. He said he knew that I hadn't been there, I can't remember what else he said, but basically was very kind to me considering what I had done.
This was 15 years ago and it still haunts me to this day. I can't believe I acted the way I did. I really want to contact my old boss to apologise but I'm not sure what to say or how to say it.
To be honest, reading that, while if this is on your conscience then it might be a good idea to write a letter, I think you're blaming yourself far too much. Putting someone straightfrom uni into a remote office with no real guidance was unfair on you. I work remotely, but that's after quite a few years in the job and with regular contact with my boss and a wider team, and usually reasonably defined goals/tasks - the situation you describes sounds like recipe for disaster.
Your manager should be writing a letter of apology to you for putting you in an impossible situation. Well done for "fessing up to your boss. You did nothing wrong. Perhaps write a letter to yourself explaining why you did what you did, and then burn it. ALternatively I suppose you could talk to a counsellor.... I'll be interested to see what suggestions people have. PS: I wonder if a bloke put in the same situation as you would still be beating himself up 15 years later. Probably not is my answer!