Few things are more painful than loving a 15-year-old girl, particularly when she is your child.
Ask any mother who has been through a daughter's adolescence and she will nod in sympathy, maybe even give you the hug you have been missing.
It will pass, friends tell me.
You know it in your head, but your heart is a torn punching bag with the stuffing falling out.
After more than a decade of nurturing and feeding, picking up and dropping off and helping with homework and braiding hair and supervising play dates and fighting battles and holding hands to cross the street, you are suddenly shut out.
The bedroom door is firmly closed. Every now and then, I knock and go in, but I always feel like an intruder.
I yearn for those nights when my daughter, Paulina, couldn't sleep and I spooned her tiny body in the recesses of mine, her warmth commingling with mine, putting us both into a coma.
These days, I barely see or talk to her. She's busy with school and when she has free time, she would rather be out with friends.
I get it. I hear snippets of her life ringing from her upstairs room, conversations and laughter, favourite songs occasionally played in the car from her iPhone.
When I try to connect with her, it backfires.
A few months ago, she cued up The Rain Song by Led Zeppelin, one of my favourites when I was her age.
I told her so and she didn't respond. I made the terrible mistake of attempting to play it for her on the acoustic guitar when we got home. She was learning to play the guitar and I thought maybe she'd want to know the chords.
She barely stayed for the glissando intro, then fled upstairs. As far as I can tell, she hasn't listened to Led Zeppelin since.
I know. I know. I remember how I treated my mother at that age. Not wanting to talk to her, much less walk near her on the pavement.
I became enraged when she secretly looked in my diary, obviously snooping for information about my life.
But now that I have my own teenage girl, I realised for the first time that my mother wasn't looking for anything incriminating.
She was simply looking for me. Trying to catch a glimpse of the girl she had given birth to, the full-grown person she had nurtured, who was walking swiftly away from her.
From this vantage point, a new, sadder realisation struck me: I no longer saw Paulina in her natural habitat, telling jokes or even crying with those whom she was close to.
I was losing her to the world. Which is the point of your children growing up. If you do a good job, they go out into the world and make a life.
Then, a few days ago, I bumped into Maddie, a friend of my older son, Dean, who is away at college. We chatted about how school was, if she'd spoken to Dean, if she missed home. Then, she asked: "How's Paulina?"
"Good, I think," I said, mentioning that she was taking a class at the International Centre for Photography. "She loves photography. Hates her maths teacher."
Then Maddie, eyes wide, asked: "Have you seen her Instagram feed?" I started to panic.
All I could think of were other parents I had spoken to whose daughters' feeds were filled with revealing photos. Parents who had to take their children's mobile phones and computers away because of inappropriate posts or texts. I thought. Here it comes.
"No," I said. "Why?"
"It's amazing," Maddie said. "She's a great photographer. She has more than 1,000 followers."
I had never asked to see Paulina's feed. I didn't even know the name she used. But 1,000 followers?
That night, I got up the nerve to ask Paulina if I could follow her on Instagram.
Miraculously, she said yes, shrugging as she walked up the stairs to her room. I grabbed my mobile phone and, suddenly, there it was: Paulina's life. In black and-white and full colour.
There were photos of her girlfriends hanging out in the bathroom at school, friends goofing around at a spot they call Venice in Gowanus, where Brooklyn teenagers go after classes, and a great shot of all the boys' skateboards piled straight up in someone's hallway.
An artistic shot of an empty, rumpled bed in a friend's room in Rockaway. A lonely place setting in a Japanese restaurant. Not just photos, but beautifully framed photos. Taken by my daughter.
Social media has been blamed for ruining American democracy, shortening our children's attention spans and undermining the fabric of society.
But through it, I was able to be with Paulina out in the world again, to see what she sees, to virtually stand beside her and witness the people and places she moves through, in nearly real time. Not in a parent-policing role, but in a wonderful-world sort of way.
There were gorgeous landscapes from Orient on Long Island, where we've spent part of every August her entire life, lovingly captured with the title My Happy Place.
Tender close-ups of Dean. A picture of her best friend bandaged in a hospital bed after a seizure last year.
"I love you," Paulina wrote under it.
And photos of a trip we took upstate last winter, blue windows looking out onto the evening's snowy landscape. It was the same view I had experienced, but perfectly archived for eternity.
Then, there was the photo she posted of herself as a little girl among autumn leaves, wearing a chequered skirt, pink leotard and green high-tops.
"Wish I was still a little kid," the caption read.
So, I wasn't the only one.
- The writer is a journalist and the author of Murder In Matera: A True Story Of Passion, Family And Forgiveness In Southern Italy.