Responsible

So where along our lives do we become adults? Is it when we are 18? We finish high school or college? We get our first full-time job? We get married?
I was justing thinking lately about how I spend my time. I am becoming very responsible with everything I do. I feel like I am becoming an adult. I don't feel right about spending the whole day wasting time on one thing or another. If I become idle for too long I long for something else to work on. This is great for work, but horrible for relaxing.
I love the good ol days of spending a whole weekend not caring about what I did at all. Now it seems that everything is work-work-work. Work to make money to have a car and house so you can go to work. I feel I am becoming a work-a-holic. Working 6 days a week, and coming home and doing work for my internship 4 nights a week.
So who wants to go out and have a picnic? Go fishing? Play paintball? Walk around, just sit outside for awhile and relax. This is my dream. And it looks like my temp assignment is tapering towards an end so I may have some time for these activities soon before I am re-assigned.