It can be terrible to be in a creative rut. Your project is probably swallowing you whole, consuming your life and allowing you to concentrate on little else.
I posit that this mental torture is being caused by the fear of judgement. Therefore the solution that I would recommend is to publish.
“Whether ’tis nobler in the mind to suffer, The slings and arrows of outrageous fortune Or to take arms against a sea of troubles, And by opposing end them?”
(William Shakespeare in Hamlet)
Publishing is an act of defiance against the fear of judgement. It does exactly what you’re terrified to do, it exposes you to be judged.
Then once you publish you’re free of the mental agony. You can wave goodbye to that painful project and start a fresh with a clear mind and a determination not to repeat past mistakes (I hope 😁).
Yes publishing might attract criticism but I think this potential negativity is the lesser of two evils compared to the internal mental berating.
