Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats.
At some point, I had to make a decision: I could practice more and become a really great guitar player or I could work on writing better songs. There are only so many hours in the day, and I found writing songs more fulfilling than working on becoming this virtuoso guitar player.
I wasn't always a writer. When I went to college and majored in fine arts, I was a painter. Then I was a stay-at-home mom.

