I served a term in the Marine Corps, graduated college, married & divorced all by the time I turned 25, at which time I was ready to just relax with the 40 hour work weeks and no commitments. Now in my 40s I'm very comfortable with other factors in my life, so I'm giving dating a bit more effort.
I'm a bit like what a friend of mine coined as a term, "macho nerd", equally comfortable at a sci fi convention or a shooting range, watching Harry Potter or an MMA fight. I can be serious when I need to be, intelligent to a fault, and can come off wierd sometimes (I describe my sense of humor as "in my own world" style, sometimes people dont get it, but I do). I can be extreme in my tastes, from New Age music to metal, "When Harry Met Sally" to "Saw", poetry to "Game of Thrones".