I don't know if "old" is the appropriate adjective, but over the last few weeks, possibly months, I've felt it. Or perhaps it's better described as "responsible". I think it may have something to do with being married for so long, living in a house, having two kids - one of which is in school. The days are filled with errands and work (which is taking up a lot more time than I expected), making sure Logan has his homework ready for school, Carter has enough winter clothes and being excited about purchasing new furniture. Maybe that's it - the tell-tale sign that you are "responsible", being excited about an ottoman.
Or maybe it's the new gray hairs I've found in the last two days. That makes me feel "responsible".