It's easy to be discouraged when we dwell on these things. Here is a practical little list of things NOT TO do as an author. Feel free to add to this list by leaving a comment!
How to Feel Miserable as an Author (Or, what not to do as an author. Underline any that currently apply.)
1. Constantly compare yourself to other authors.
2. Talk to your family and friends constantly about what you do and expect them to cheer you on.
3. Base the success of your entire writing career on one book.
4. Base the success of your entire writing career on book sales.
5. Undervalue your expertise.
6. Let money dictate what you do.
7. Fret over any negative reviews and rejection letters.
8. Bow to societal pressures and write what the world wants instead of what God wants.
9. Set unachievable/overwhelming goals, to be accomplished by tomorrow.
10. Stop writing.