Apologies if my post came across as personal suffering - I certainly don't want any pity! I didn't intend for it to be too negative - I was just being honest and got a bit carried away! This has been a very, very hard slog and I realise most people on here are going through the same thing. I would never write something like this on a more mainstream site - it was written for hackers in the same position as me so I felt I could afford to be more down to earth. Having said that, I take your point - it was probably too much for a "Show HN" where the main focus is to sell the app.
I agree with everything you say about the word "loop" and me being "too close to the product" and not knowing how to sell it. I will spend as much time as I can going following this and all the other advice on here to learn how to sell this thing. It's all new to me, but I am determined to learn it all.
Thanks again, excellent feedback.