As you've mentioned, living within your comfort zone is likely a part of the problem. Don't see stuttering as something that holds you back. Yes, it's difficult and we stutterers would rather have a cure but remember that many people who stutter have gone on to do great things. Start challenging yourself, I believe the more confident you are the less your stutter impacts you. Aside from your stuttering, pushing your boundaries alone will help you in other aspects of your life.