That does sound like a long time if you're a green beginner, but it never hurts to ask around and see what's available and what you'd be able to do.
Alwaysbehind - I was a homeschooler for all of "highschool". Parents aren't totally necessary to "teach" a homeschooler. After 6th grade when I left public school, I basically taught myself. My parents helped me, kind of in the same way my friends do: quizzing vocab and holding flashcards type stuff, but there was never any kind of "Sit Down and Pretend Mom is the Teacher" mentality. I hid in my room and taught myself, and if I hit a roadblock I asked for help. It's a lot of freedom and doesn't work for everyone, but I survived, "graduated," did well on my SAT's, and got into a very good private college on (comparatively) very little money.
@ Wishingforahorse, you've got a great opportunity in the homeschooling, and as you get more into horses you'll appreciate the freedom and flexibility of it more and more.
Being nosy... have you ever read The Teenage Liberation Handbook
? If you haven't, it's worth a read even if you're already homeschooling.