Writing is one part of the job, publishing and promoting your novel is another part of the business. One that you have to learn you may need help for this.
Grow a thick skin. Perfection is on another planet light-years away. Your novel will never be perfect, you WILL have a few bad reviews. If you go back to a paragraph or chapter you wrote a few months ago, and it still makes you smile. That's good writing you can't please everyone -- but your writing must at least please yourself.
Writer's block is your subconscious telling you that something may be going astray. I take a break, a few days off, read a biography, science fiction or some novel not in the genre that I am writing. When I get back to the writing I see things differently and it always helps me to 'unblock' .
As a human being, I've evolved over the years (hopefully for the better) I can see that the characters in my novels have also evolved with me. More open to expressing inner feelings, more open to other cultures, to other life choices. Montreal is a very multicultural city and an LBGT-friendly city and that's reflected in some of my writing.
Reviews are like fresh air to the writer. It takes months, sometimes years to write and polish a novel. I always look forward to readers reviews, even bad ones may give you a different take on how your written word was interpreted. It's a continual learning process that I know I will never fully master.
At the base, the plot has to make sense, be intriguing enough that the reader will follow, and the characters have to be interesting, --- but above all, good writing is good editing. A professional editor is a must if you are going to turn out a quality novel.
I don't read--I devour books. One day, I realized that I was critiquing the author of the novel that I was reading. I said to myself, "Self, maybe you could write your own mystery novel." I wrote a few short stories and quickly found out - - it wasn't as easy as I first thought. I enrolled in online writing courses and a few years later I started turning out prose that won a few small contests, some short stories were accepted by online magazines. That pushed me to write my first novel.