At the end of my last visit home to Philadelphia, I boarded a train with my ex’s wife. We were on the way to her house, where I would stay overnight and feel terrible the next day. “I’m so excited for your reunion,” Allison said. “I’ll take video again.” I said I’d love that. “And honestly,” she added, “It gives Ross and me a much-needed break.”

I was more than happy to give them a breather. After all, Sydney can be a handful—she’s the dog Ross and I got when we were together, and with whom I do my best to maintain a long-distance relationship now that I live in L.A.

Any time I fly home to visit my parents, my sisters, my niece and nephews, and childhood friends, I also visit Sydney, because she is just as important to me.

When I try to explain to people my insistence on spending a night at Ross’s when I visit my hometown, most find it strange. But Sydney is my other half. And while Ross and I were never meant to be as a couple, Sydney was always meant to be my dog.

She and I are both dark-eyed, with the same matted black hair. We are both nervous. I tug at my curls; she bites her belly. We both grow agitated at the sound of a skateboarder approaching, and could both survive on smoked salmon and peanut butter alone. Our favorite way to spend the day is people-, dog-, and squirrel-watching by an urban fountain, followed by a brisk walk along a concrete path. We are fiercely loyal. We impose order where there’s disarray. At the dog run, she corrals canines to chase in the shape of an oval. At home, I assign stray items to their designated zones. But we have one major disconnect. We live 3,000 miles apart.

It’s hard to believe that a time in my life existed when I didn’t want Sydney in it. Almost 13 years ago, for my 24th birthday, Ross brought her home to me. She was a yippy, energetic puppy, and Ross had decided to adopt her the very week I needed to record a demo of original songs. I had planned for years to use my savings to record with a producer in Los Angeles—and I needed to send him a rough copy of my music in preparation for my sessions with him. With Sydney constantly shrieking, it was nearly impossible to do.

By then, Ross and I were four years into our relationship and it was already deteriorating. We argued more than we laughed. And while Ross had been a supportive partner, I was not capable of appreciating him at the time. He was 35 and ready to nest while I was a young 25, still fumbling to figure it all out. A year later when we split up, I agreed to let Ross keep Sydney because it seemed best for her—as long as I’d retain visitation rights.

For the next eight years, I’d take her a few nights a week. I loved when Ross traveled because it meant I could keep her longer. And he never minded if I wanted to pop by for a run to the dog park. This went on until I decided to make the big move to the West Coast with my fiancé, Alan. We had met on the set of a television show in Philadelphia and had dated long distance for two years. It was time to choose my love for my partner over my love for my dog.

When I contemplated what to bring to Los Angeles, my mind returned to an image of Sydney as a pudgy, fluffy puppy, mostly charcoal black with tan eyebrows and white front paws that looked like wearing one sock up, one sock down. I wanted to take her with me. I wanted to so badly. Alan offered to drive across the country to get her. When I ran the idea by Ross, he said, “No way. It would be like giving up my child.”

I wondered how she’d feel. What if she thought I abandoned her? Unlike the people I was leaving behind, she couldn’t call me to catch up. She couldn’t buy a plane ticket and visit. She couldn’t comprehend that 10 years ago, her “parents” realized they weren’t right for each other romantically, but friendship and shared custody could work. And this time, I was moving a full country’s distance away.

Through his use of brain imaging technologies to understand canine motivation and decision-making, Gregory Berns, MD, PhD, a professor of neuroscience at Emory University, has reason to believe that dogs do miss us when we leave them. Even though a part of me already sensed this, hearing it breaks my heart.

Leading up to the time I decided to wedge an entire continent between Sydney and me, my friendship with Ross had flourished, and in ways I never expected. Our unpleasant time together as a couple felt like a past life. Not long after our split, I helped Ross build his OKCupid profile, where he met Allison. A year later, both of them helped me survive a cataclysmic breakup. I needed Sydney and they let me have her for a few months. She slept in a “U” shape around my head, until I felt strong again. Years after, I took Allison out for a bachelorette celebration. And years after that? On a weekend Ross traveled for work, I stayed with Allison and their two young children. Once we tucked the kids in, we stayed up chatting like longtime friends—because that’s what we had become. And on this past Thanksgiving trip, I flew with Allison’s 91-year-old grandmother from San Diego to New York and back. Sydney’s parents and siblings feel just as much like family as she is.

But when it was time to confront my Los Angeles move, a familiar fear arose from years ago, when Ross and I broke up—what would I do without my dog? I wondered how a rightful dog-parent was determined in pet custody disputes. Madeline Marzano-Lesnevich, President of the American Academy of Matrimonial Lawyers said: “I can see down the road, a vet being called as an expert to opine on who has bonded more with the pet. What better way to tell than to see who the dog runs to?”

Sydney would run to me—but she’d also run to Ross, his wife, and their kids.

Finally, Allison and I reached the house. When she unlocked the door, a 50-pound 12-year-old Australian Shepherd barreled toward me, howling from the bottom of her chest. I crouched down to her. I felt her wet, bristled tongue whisk my face. She performed her miss-me dance—her stout, wooly body throttled into me, then tottered away, as she whimpered and wailed. She repeated this process and I caught the rhythm of it, catching her fuzzy snout in my hands each time. Allison, like she has before, took a video for me to keep.

It had been a year since I’d seen my dog. Her brown eyes were cloudy with the layer of film that sets in with age. Her fur was rigid. Her howl raspy. I leaned into her and hugged like anyone would when reuniting with a loved one they think about constantly, from way too far away.

In dog years, Sydney is 84 years old. I don’t know how many visits with her I have left, so that evening I slipped away from the family to hang with her in their guest room. I must have fallen asleep, because I woke up at dawn to her nudging nose, and a molten trail of sunlight across the room. I zipped on my long, puffy coat, tied up my boots, and took my ex-dog out for one last walk until my next visit in six months. When we went back inside, Ross was frying eggs. “Every morning, when she wakes me to take her out at 5 a.m., I reconsider giving her to you. She’s like a permanent alarm clock.”

I hold my breath, and then I complete Ross’s thought for him: “But that would be like giving up your child.”

Back home in Los Angeles, from my balcony, I can see the young couple that lives in my building take their Aussie puppy out for a walk. She has Sydney’s same markings. I watch her hurtle toward smiling strangers. I see her dash with newly discovered slack from the leash. I run downstairs and she runs to me too. Can she sense my void? Like Sydney, she playfully nibbles my nose. Then she watches me as I walk toward the door.

Before I go inside, Ross texts me: “What are you doing the third week in August? Do you want to stay with Sydney while we go on vacation?” I am giddy at the thought of a week with my dog, just the two of us. I don’t even need to think before I text yes. I am engaged and have built a life with Alan in Los Angeles. But my heart? It’s in Philly, with Sydney.