Ambush, I was prepared. Partly due to schooling, partly due to life circumstances and partly due to my mother.
My high school gave me a forum to debate/understand the depths of Torah. I questioned everything and the good teachers showed me that it was ok to question and search for answers (ok I had plenty of bad teachers to who did nothing for my growth). I had a few great role models to guide my path.
I also had a more challenging childhood than most of my friends which paved the path to adulthood.
My mother did the best she could to make sure I was responsible and able to stand on my own two feet. She gave me an excellent grounding and I credit her with most of my growth. My hashkafa and values today are pretty similiar to when I left high school 9 years ago (wow!) – that doesnt mean I havent grown in many ways though.