You don't need anyone to tell you how to live you life, and why should you? You know yourself better than anyone else and you know what's best for you. You're your own boss, and you like spending time on your own, thank you very much! You know that you alone are responsible for your successes and your failures.
Your strengths: Your self-assurance and sense of responsibility give you strength of character, and you inspire confidence.
Your weaknesses: Your self-confidence and solitary nature can make you come across as stuck-up to those who don't know you. Try and open up to other people a bit more.