Erin took a deep breath and looked at me. Then she got up and crossed the room and gave me a hug. I felt the warmth of her body against mine, and though I’d been holding her at the lake that afternoon, this Erin felt completely new.

“I’m glad you’re saying this,” she said into my ear, “but it’s going to take time for me to believe you. I need to actually see you making changes.”

And though we didn’t kiss, just stood in the light of our bedroom, I could feel her love again, and when she let me go, instead of pulling tubes or turning on PlayStation, I decided to do some more push-ups in the living room and get into shape like that other me in Erin’s world.

Things got better. I’d see Erin at the lake house during the day and spend evenings with the other Erin at night. We cooked dinner at home and joked like we used to, and though we hadn’t kissed yet, we hugged more. Meanwhile, in that other reality, Erin and I spent hours naked in bed pleasuring each other. Afterward, we lay together like new lovers, talking about a future where we’d use Donnie’s discovery as a travel agency to teleport us to a multiverse in Paris or Morocco. But it was also true that life was getting complicated. Now that things were thawing at home, Erin was sending me romantic text messages that I couldn’t answer for hours. I asked Donnie to field them for me.

“Sexting isn’t in my job description,” he said. “You know what is? Quantum physics research. You should try it sometime.”

“Please. I’ll write you notes you can use. Just text her back so she thinks I’m here.”

And maybe everything could’ve worked out, the four of us functioning together across multiple dimensions—Donnie fielding texts for me, Erin and me happy at the lake house while the other us healed our past in the present—if only reality hadn’t started getting weird. Like how Erin was humming a dub-folk melody while she worked on her thesis, the very same song the other Erin had been playing for me earlier that day. Or how she began talking about getting a tattoo, a firebird on her forearm. And then there was the night when she woke me. I was still sleeping on the couch, the moonlight coming through the living room window, and for a moment in my half-asleep state I thought I saw the frozen lake outside and couldn’t remember whether I was at the lake house or our apartment.

“Luke?” Erin said from the doorway. I blinked my eyes and saw her guitar in the corner of the room.

“Yeah?” I said, rubbing my eyes.

“Can you come back to bed and hold me?”