Is it bad to hide your achievements?

Unfortunately life consists of succeeding and failing. All of us fail at something. Your family and friends SHOULD be proud that you would even attempt something as difficult as writing a book. I would personally be VERY proud of someone I knew trying to achieve their goals, no matter what the goal may be. That doesn't mean "blowing your horn" every time something good happens, but if you are proud of something, let your friends/family know. You may be surprised ! If they continue to be negative, that is their loss. In reality, they may be jealous of your zeal for life and desire to succeed. More people should be like you. Good luck on that book!!