How/When did you transition from boy/girl to man/woman I've yet to have my coming of age. But I transitioned from child to man when my parents got a divorce. It was now my obligation to be the man of the house. I stated becoming self dependent, and that honestly felt great.
Hmmmm, a very philosophical question! I guess for me it was when I moved out of my Dad's place when I was 19 or so. For the first time I had a good job, and now a place of my own. Well, kinda. Me and some guys from work rented a house. Yeah, that makes you do some growing up for sure. My parents got divorced when I was in high school. It was an ugly divorce that destroyed my Dad for a while. It sucked balls!
I'm still in high school, but I became of age about a year ago when I got my First Class rank and became the Administrations Officer of my Junior ROTC unit. I now say lead me, follow me, or avoid me to the platoons.
Tough question. I guess I really became of age when me son was born. I was 22 and before that didn't really have many man responsibilities outside of the typical living an such. I moved out at 18 and really didn't look back, but taking care of another human being really makes you step it up.
I can't say there's been a definitive time/event/milestone that made me aware of that I've come of age. There's been a lot of stepping stones (performing live for the first time in front of a decent-sized crowd, earning Eagle Scout, graduating high school, dealing with college stuffs, being in a relationship, etc). It's a gradual thing for me.
At this point in my life, I'd say my coming of age was when I went on a 10 day trip to China with my school. It was the first time I had been independent from my parents for more than a couple days, and the first time I experienced much independence. Who knows what I'd say about it in a year or two, though. I may very well not have come of age at all yet.