Picking up my race packet last year.

I will run my third half-marathon on Sunday, almost one year after my first. My body is in drastically, almost frighteningly different shape this time; my mind and motivations are, too.

Running through a failed relationship and post-grad angst, I relished the psychological aspect of miles and miles and miles. I logged 60-70 miles in a single week sometimes, running 12 or 13 miles after a full workday, perceiving it as the pinnacle of dedication to my health. The folds in my clothes multiplied that summer and fall; the more miles I ran, the less of me existed. I weighed 105 pounds when I crossed the finish line Oct. 18.

I felt invincible; running was the closure I needed, the structure I needed while adjusting to my first big-kid job. It’s not what my body needed. Not then, anyway.

Running is a hobby, coping mechanism, lifestyle and obsession for me. That spring, summer and fall, it was also a trigger. Training triggered my then-dormant celiac disease, shocking my body into losing 20 pounds and into months of crippling exhaustion.

In November and December, I could only run on the treadmill for five minutes at a time, dizzy and in denial. I loved running. It made me feel strong and in control. The psychological benefits I craved faded into painstaking 20-minute workouts that winter. I clicked the arrow button on the treadmill down and down and down, the workout facility in my basement whirling with each attempt to push myself, to search for the euphoric feelings running owed me.

As I lay in my hospital bed in January, blood cells filing their way down the IV line, I blamed running. I had put in the time and work. It owed me strength and stamina and self-esteem.

That spring, I visited specialists, endured six weekly IVs and broke up with bread. I started running again; I had my second half-marathon in April, after all.

Autoimmune disease is the ultimate betrayal, as the body self-destructs in cunning fashion. Running hadn’t betrayed me, and it didn’t owe me anything.

This year, running and I are a team. I focused on training enough but not too much. I weigh 125 now, and my clothes fit again. I stopped eating gluten (RIP focaccia bread, ILY).

I’ll run 13.1 on Sunday with renewed health and understanding of mind and body. Running, in all its gritty generosity, serves both. I don’t owe running a PR, a medal or even an apology for my naive gluttony of that runner’s high.

We’re a team now. Running needs me to be there at my best, and I need running to keep me balanced in mind and body.

The only thing I might owe running is a post-race toast.