I know this taste.

I first experienced it in the summer of ‘79, before my freshman year of high school. The summer I turned into a Type 1 diabetic.

Before then, at a Michigan middle school, I would play pickup basketball daily, usually with a huge plug of Bubble Yum bubblegum wedged in my mouth that I’d smack incessantly and obnoxiously as pre-teens do. It was my Popeye spinach; the sugar high fueled me until darkness called the games.

Then I turned diabetic, and sugar was out. I’d still play daily, but something was off. How can it not be when a fixture in your life is suddenly gone forever? It’s an unmistakable, undefinable flavor, the taste of vacancy.

As I got older, I’d realize it’s not an uncommon thing. It happens anytime someone you love suddenly dies. It returned in 1999, when my dear friend Libby Hatch, who had offered one of her kidneys for a transplant I needed, died in a motorcycle crash three weeks after the profound gesture.

And it returned this weekend, when I gave JD away.

It killed me, giving her up. But I found myself falling daily while walking her. Since the transplant, I’ve suffered severe orthostasis, an abnormal drop in blood pressure that occurs when you stand that can lead to fainting. And while I never lost consciousness, I would “white out” as my vision faded and dizziness swelled. I’d collapse in the dog park, on a sidewalk, in my kitchen. Just wrestling a dog vest on JD — who is not yet five months but already 50 pounds of muscle and joy — left me gasping.

People would come up to me at the dog park, where I routinely had to sit in dirt while I waited for the cobwebs to clear, offering to help me on my feet.

Last week, on the day I fell twice, I called the dog walker, Lauren, and conceded the once-unthinkable: I didn’t have the health for a dog that healthy. I choked down sobs and told her, I don’t think I can do this.

Lauren, who manages dozens of dogs with a team of animal lovers, told me she and her boyfriend would be willing to adopt JD. They already had two dogs, and JD would get daily walks with the “woof pack” at the park. I could still see her five days a week. More importantly, JD would get the company and exercise she craved. And deserved.

Finally, I agreed. Lauren brought Jack over, and they all played in my backyard. As they laughed and sprinted through the yard — something I rarely can do — I began to lose it. I felt like shit. My sniffles punctuated JD’s playful growls and yips.

They sensed it, of course, and assured me: If I wanted her back, or if she somehow wasn’t a good fit for them, they’d return her in a heartbeat. “I know it’s hard,” Lauren said. “I can’t imagine giving up one of my babies.”

I could. This fucking body has repossessed much.

As they walked to the front door, JD in happy tow, they repeated their promise: Make the call, and she’s back here. I couldn’t muster a response, just a teary wave as they closed the door behind them.

The next day, I awoke to an empty house, which I guess was fitting; I was empty, too. I dragged to the tub and immersed in defeat. I thought I’d beaten this goddamned disease with the transplant. But you never defeat it. You’re always shadow boxing; it’s just a different shade.

But suddenly, a ding. Reprieve!

It was Lauren, texting to say that Friday night was a disaster. Her dogs apparently were offended at the very existence of JD (particularly the older dog), and made everyone’s existence a living hell. She would need to return JD, she said, but would continue to help me find a “forever home” for my girl.

The news jolted me out of the water like I’d dropped a toaster in it.

It wasn’t me. I may be broken, but I’m not a bad parent.

Lauren was similarly devastated; she’d come to love JD, too. But deep down, I was overjoyed. Knowing that a young, healthy couple found her energy a challenge meant that maybe I wasn’t so broken.

And now, she is back home with me. And I feel a renewed strength, a resurgent health, an enlightened sense of sight.

I may still have to find JD a home. Some one day, I may still have to concede to that jagged vacance. No matter its form, diabetes is a relentless mobster, constantly collecting on the vig.

But not today.

Today, I am a good dad. Today, I can offer her a good life.

We don’t always get to choose whether to alight the No on our Vacancy sign.

But when we can, it’s as sweet as bubblegum.