My dad( and mom) gave me a thourough lesson on Thomas the Tank engines, showed me aroudn steamtown once, and I was hooked. They say they'll never do this again.
Did they say why they would never take you to Steamtown again? My three year old son loves trains, and did not want to leave Steamtown at all. (Then again, his second word was "train").
My mother and grandmother tried to break me of my love of trains, both claimed that I would "grow out of it". If anything my love of trains has only grown and expanded to include Trolley cars as well.
Express to your parents that you love trains, and hopefully they will understand and encourage your hobby.
In any event, you are at the right forum to discuss ferroenquinology (study of iron horses).
Keep on the right track!
So many scales, so many trains, so little time.....