The Necessity and Discomfort of 'Fence Straddling'

This lyric, ‘Leave Me Alone; I’m Lonely’, from Pink’s ‘Leave Me Alone’ song – NOT the whole song, mind you – ONLY the lyric, taken OUT of context, is my teenager’s anthem line in what is the nature of our current relationship.
On the very uncomfortable fence, straddling impending manhood and the tenuous tentacles of childhood he fluctuates between “I don’t need you. Leave me alone.” and “Can’t you just sit next to me and cuddle?”. These swings can take place within moments of one another. The change coming so fast I sometimes struggle to catch up. He’s not unaware, which helps a great deal.
A few weeks ago I had to take him to the airport. He was flying, solo, for the first time to meet his Dad in Boston. I parked the car; got a pass to accompany him to the gate; bought him candy and water; fed him a full dinner; and walked him to the gate. As they started boarding and requested my son to line up, I made overtures to depart. I hugged him and was about to walk away when he pulled me back, imploring me silently with his eyes, to stay put. His entire 15 years we have poked fun about the fact that neither of us can ‘leave a tender moment alone’ and this ‘moment’ was no different. Immediately, to avert the choked-up tears that instantly appeared (mine; not his), I started singing…”leave me alone; i’m lonely, i’m lonely”… He laughed. I laughed. He walked on the plane. I cried.
There are two fence sitters in our house. Yes; he morphs from ‘almost man’ to ‘child’ without notice or pattern; but I too vacillate. I still bring him a Starbucks Frappuccino Mocha when I wake him up (yes, I wake him up) and make his school lunch (healthy food to help him focus is important to me). Before you judge or feel disdain and send me nasty comments, I also do not get involved in his schoolwork or his relationships with his teachers. He does do chores and is expected to help ad-hoc, when asked, without push back. This includes taking out the garbage, unloading groceries, cooking, and laundry. The fence sitting struggle is real for us both.
I get that this awkward process is nature’s way of allowing us to separate. Someday, all too soon, my son will not live here any longer – much less need me to drive him anywhere or make him school lunches. Someday, all too soon, we both will come down off the fence and probably wonder… was it really that uncomfortable at all?