Hi, James.
Sounds good!
But I can relate to the feeling that you're writing the same song over and over again.

Some thoughts you can ignore...
I heard you
almost sing on
"with golden hair". So I know you can sing a
little. And a little is all you need.
How about just singing the chorus? And by "chorus", I means something really simple, like repeating
"You don't know" or
"You broke my heart". Not many words, only a few notes.
Make the chorus more up-tempo than the verse, so it's a strong contrast with the verse. Drums, shakers - all the standard tricks that pop songs use to give the chorus a lift.
You could even mix the sung part with spoken word in a call and response, such as:
(sung)
My one mistake... (spoken) Not telling you.
(sung)
My one mistake... (spoken) What can I do?
(sung)
My one mistake... (spoken) That's my one mistake.
That way, you're only singing a few notes - but making them count!
I've mentioned William Shatner's "Has Been" album, which has the "problem" that he doesn't sing. For example:
That's Me TryingAnd if you don't feel comfortable singing, you can do what Shatner did and have someone else sing it for you.
