Hi Maddie! Be sure to 'register' on our "Class of 2011" thread under "Thru-Hiker Classes", you'll be added to the list of over 200 names (and growing) and other hikers starting around your date might contact you or visa versa.
I'm a mom of 3 boys - 19, 23, & 27; I can totally appreciate where your parents are coming from. Even though I'll be starting the trail 'solo' in March, I'd be a little nervous if my 19yo were doing the same. Very hypocritical I know, but we're parents, we love you so we worry.
Like the others have said, there are hundreds of people starting the trail each week in march and April. You'll find a group who's company you enjoy and who can keep up with you!!! I have a feeling you have a good head on your shoulders and you'll do just fine....
TF