Just caught up on all this (had to skip a bunch of the messages though - headache central) and though it's easy for me to say as I am not one of Marty's victims, I do feel sorry for him and hope he gets the help he needs. Who knows what he's been through in his life to resort to this type of behaviour; threats, lies, outing punters and WGs, seeking validation from strangers on the internet
Can't help but think that if you or I were born Mr Marty Mcfly/Colombo/whatever, with the same brain, and had been through the same things, we'd be prone to the same mistakes. Should he be held accountable and punished for what he's done? I think he definitely should be made to see the error of his ways, but after that there IS hope for him to lead a more positive, productive life where he realises that self-worth comes from within.
I don't wish to offend those who have been affected by Marty or excuse his behaviour, I know there's no way I'd be writing this if he'd fucked with my life. But as an outsider I'd like him to get some help. There are murderers, rapists, woman beaters out there who have turned their lives completely around. So Marty, if you're reading - it's not over. Face the consequences of your actions, then start fresh.