Anyone who has even a remote desire to go abroad should decide to do it, in my humble opinion anyway. If for some reason you can’t last the semester or year and you have to come home, what’s the worst that can happen? You lose one semester of school and graduate when you’re 23 instead of 22. In the scheme of life, that’s not that big a difference, and the chances of that happening are minimal.
One of my biggest fears when I made the decision to go abroad was that I would lose my good friends and be really far out of the loop when I returned home. First and foremost, your being abroad shouldn’t change anything. You can still talk via Skype and phones and, if your friends are true friends, they will be excited for you to go and do something with your life, as well as be understanding when you come home.