I am impressed.
When I was 17 and still in high school, I did things because my parents said so. Simple as that. I wasn't strong enough to stand up to anything or really protest anything. (I've come a long way since then.
) I think I just felt dominated by my parents and older brother and sister. Eh.
I've been more or less vegetarian since January. With the exception of giving in to some wings a few times, and eating some (free) meat lasagna (I picked the meat out; Had I not accepted the full pan of lasagna, it would have been completely thrown out), I've been meat free.
I don't think my parents, whom I rarely see, have figured it out. I think I told them, though. I've said things like, I had a veggie burger and Andy (my husband) had a hamburger. The last times we had meals together, in April, I ordered the veggie burger at TGI Friday's and had a cheese and lettuce sandwhich at the family dinner my sister had for her daughter's birthday party the next day.
On my husband's side, I also don't think they figured it out yet. My FIL, while usually sharp, does not pay much attention to his children's and children-in-law's eating habits. (His are pretty gross, which I thought before I went veg*n.) I just don't think my MIL has figured it out, or just doesn't ask. (The last time we were there for dinner was the week I learned how cheese is made, thanks to "Who Wants to Be a Millionaire". My husband, not knowing that I had decided to start eliminating cheese [I think he thought me weird for that, but he still loves me] phoned his mother to have her order the pizza, complete with cheese. I was hungry and almost ate one, until I saw how greasy it was and realized that there was little sauce under the cheese. Later that evening, though, I did have a bowl of Kix and Total.) I told my husband's older sister and she thought I was weird. (She also thought me weird when I also told her that I never liked potato chips, which were not often seen growing up). However, she was impressed that I had quit smoking.
Stick to it. I'm guessing, at 17, you're close to graduating and (hopefully) going off to college, at least. As I said, I think your strength your beliefs and being able to stick up for them to your parents is way cool.