When I turned 18, I asked my parents if I could go visit a girl I was semi-dating 2 states away. They said no, and I protested and gave them every reason why they should trust me (I would be staying at her parents house, gave an entire list of things we would be doing as well as where I would be on what day, told them how I could afford to go and pay my own way, assured cell phone would be answered any time of day, gave them contact info for everyone i knew including her parents, brought up the fact that I had never given them a reason not to trust me other than being a teenager, etc.). After a day of thinking about it they agreed, it was sort of like them handing me the reigns for a little while to see if I lost control. But I didn't and after that their trust factor went way up, I had graduated to adulthood.