The pain of abandoned projects - I totally share this feeling. But your friends may be right when they say that, despite it all, a ton has been achieved. Keep going Tom!
... to friends about this on a walk the other day their opinion was that I need to cut myself some slack and realise how prolific I've been. I do agree with them. But I also feel the pain of abandoned projects, the pain of not writing when I should have been writing because I had to clean up a mess.