You can devour the best writing books under the sun, you can know what constitutes good writing, you can recognise and understand exceptional work when you read it, you may even be able to critique and edit to help other peoples' writing shine; you may live wildly, have broadened your experience and developed your imagination but when faced with the blank page of your manuscript, all that means nothing - at that moment, and for every moment you face that screen, you stand alone with your inspiration and talent - these are the things that limit you, restrict you, that define the boundaries of your creativity.
Trouble is, inspiration and talent cannot have rules applied to them, you cannot learn them from books or buy them down the stationary store. If anything, all you've ever read or learned can stifle and restrict those things.
So what the hell do you do about it?
Transcend the Rules
Become so fluent in the mysteries of the craft you can dismiss them at will.
F*ck the Rules
Utterly ignore everything you've learned and read about writing, and just write the damned story.
Forget about the Reader
And write for yourself – write for therapy, write for your own excitement and titillation – write what floats your boat and turns you on. Chances are what works for you will work for others, and if it doesn't, you'll have written something truly unique.
Forget about the Publishing Deal
Who cares what the establishment gate-keepers like or will represent? Truth is, they don't really know what will sell – they understand the industry, but they know no more about the human condition than you do – in fact less, because that's your job.
Forget about Validation
You can write a best seller and still get slammed by the critics. You can write a critically acclaimed masterpiece that no-one wants to read. You can write the best novel you can possibly write and no-one wants to buy it. Or you can not write at all.
Writing isn't a living, it's a way of life, and you will do it no matter what. Once you accept that, the rest is easy.