I'd rather travel alone. In my opinion, being alone is the only way to fully enjoy a journey. When you set off, I think you have to experience your reaction when facing a situation that is partly or completely new for you. You are expected to be wise and responsible for yourself. So you have to face with your strengths and weaknesses. Moreover, being alone allows you to meet other people and to improve your speaking skills and to open your mind to new cultural horizons if you're abroad. Obviously you may happen to miss your family, your friends, to be homesick, but I think that travelling alone is an overwhelming experience, that everyone should try.