Double Standards

I find it interesting that as a PA student doing my rotations, many people are willing to share information and look to me for advice just like they would for someone who is actually certified, which is great that they are so trusting and respectful. Clearly the stethoscope I wear around confers authority. Others prefer to see the MD (or NP) - you know someone who is actually a Doctor. Then they will open up more.
As a twenty something, you're expected to grow up, take responsibility, be independent - you should be a bona fide adult. Watching friends experience the mature milestones of getting engaged, married, buying a house, having a baby, actually earning money and saving for retirement, I feel a bit left behind since I'm still stuck in "school mode."  I'd like those things someday - to settle down eventually and plant roots literally and figuratively. Occasionally-- on my not so good days-- I get jealous - why is it so hard to enjoy what we have? instead of pining after what others have? Anyway, I guess I've taken a bit different path than most - living abroad and then going back for grad school when others have actually started careers right out of college. The flexibility I consequently have is great - allowing me to move freely and relatively easily from place to place. It's lead to some unique experiences. That freedom and cross cultural knowledge could also prove helpful when it comes to job searching - I'm not tied down to a particular location or person so I can theoretically go wherever the right fit takes me with a skill set that not everyone possesses.
What's funny to me is how I can be treated as an "expert" by patients who expect me to know medical stuff and the same day be treated as a kid still by those who are older than me. As I've been staying with my aunt and uncle, they sometimes need reminders that 'yes, I lived in a foreign country and I'm perfectly capable of taking care of myself.' They feel the need to be protective, warning me about where it is safe to run or drive. It's kind of sweet. I know, I should appreciate their concern for my well-being, but after living on my own for a while, it's not the easiest to return to being just another kid under someone else's roof. I must say I enjoy the added perk of having a pet to come home to because I've always wanted a dog.
I suppose it's just something I'll have to get used to in this perpetual transitional state I find myself in as it's simply part of life. I just wonder sometimes when I'll ever be "adult." I'm not sure that I want to, because that can be a little scary.
What makes you grown up? Can you really set an age? 18? 21? 25?
Getting a diploma (let's be real - it's a fancy piece of paper) doesn't qualify you as grown up.
Being a parent doesn't make you adult either - it makes you a mom or a dad.  Maybe the more titles you have - mom, dad, husband, wife, chief, Dr., Mrs. has something to do with it.  At the pediatric clinic, they'll see patients beyond the set cut off of 18 years old if they are still students basically.  They essentially draw the line if you get pregnant or move out because then you may need more specialized/adult care based on the situation.