So much of the last decade had been about trying to strike a balance between my family and my work, figuring out how to be loving and present for Malia and Sasha while also trying to be decent at my job. But the axis had shifted: I was now trying to balance parenting with something altogether different and more confusing – politics, America, Barack’s quest to do something important.

The magnitude of what was happening in Barack’s life, the demands of the campaign, the spotlight on our family, all seemed to be growing quickly. After the Iowa caucuses [in January 2008], I’d decided to take a leave of absence from my position at the hospital, knowing that it would be impossible, really, to stay on and be effective. The campaign was slowly consuming everything. I’d been too busy after Iowa to even go over and box up the things in my office or say any sort of proper goodbye. I was a full-time mother and wife now, albeit a wife with a cause and a mother who wanted to guard her kids against getting swallowed by that cause. It had been painful to step away from my work, but there was no choice: my family needed me, and that mattered more.

Listen Michelle Obama reads from her book

And so here I was at a campaign picnic in Montana [on 4 July that year], leading a group of mostly strangers in singing “Happy Birthday” to Malia, who sat smiling on the grass with a hamburger on her plate. Voters saw our daughters as sweet, I knew, and our family’s closeness as endearing. But I did think often of how all this appeared to our daughters, what their view was looking outward. I tried to tamp down any guilt.

We had a real birthday party planned for the following weekend, one involving a heap of Malia’s friends sleeping over at our house in Chicago and no politics whatsoever. And that evening, we’d hold a more private gathering back at our hotel. Still, as the afternoon went on and our girls ran around the picnic grounds while Barack and I shook hands and hugged potential voters, I found myself wondering if the two of them would remember this outing as fun.

I watched Sasha and Malia these days with a new fierceness in my heart. Like me, they now had strangers calling their names, people wanting to touch them and take their pictures. Over the winter, the government had deemed me and the girls exposed enough to assign us Secret Service protection, which meant that when Sasha and Malia went to school or their summer day camp, usually driven by my mother, it was with the Secret Service tailing them in a second car.

Listen Michelle Obama reads from her book

At the picnic, each one of us had our own agent flanking us, canvassing the gathering for any sign of threat, subtly intervening if a well-wisher got overenthused and grabby. Thankfully, the girls seemed to see the agents less as guards and more as grown-up friends, new additions to the growing knot of friendly people with whom we traveled, distinguishable only by their earpieces and quiet vigilance. Sasha generally referred to them as “the secret people”.

Michelle Obama and President Barack Obama attend the national Christmas tree lighting ceremony Photograph: Pool/Getty Images

The girls made campaigning more relaxing, if only because they weren’t much invested in the outcome. For both me and Barack, they were a relief to be around – a reminder that in the end our family meant more than any tallying of supporters or bump in the polls. Neither daughter cared much about the hubbub surrounding their dad. They weren’t focused on building a better democracy or getting to the White House. All they really wanted (really, really wanted) was a puppy. They loved playing tag or card games with campaign staff during the quieter moments and made a point of finding an ice-cream shop in every new place they went. Everything else was just noise.

To this day, Malia and I still crack up about the fact that she’d been eight years old when Barack, clearly feeling some sense of responsibility, posed the question one night while he was tucking her into bed. “How would you feel if Daddy ran for president?” he’d asked. “Do you think that’s a good idea?”

“Sure, Daddy!” she’d replied, pecking him on the cheek. His decision to run would alter nearly everything about her life after that, but how was she to know? She’d just rolled over then and drifted off to sleep.

Listen Michelle Obama reads from her book

That day in Butte, we visited the local mining museum, had a water-pistol battle and kicked a soccer ball around in the grass. Barack gave his stump speech and shook the usual number of hands, but he also got to anchor himself back inside the unit of us. Sasha and Malia climbed all over him, giggling and regaling him with their thoughts. I saw the lightness in his smile, admiring him for his ability to block out the peripheral distractions and just be a dad when he had the chance. He chatted with Maya and Konrad [Obama’s half-sister and brother-in-law] and kept an arm hooked around my shoulder as we walked from place to place.

We were never alone. We had staff around us, agents guarding us, members of the press waiting for interviews, onlookers snapping pictures from a distance. But this was now our normal. Over the course of the campaign, our days had become so programmed that we’d watched our privacy and autonomy slowly slip away, both Barack and I handing nearly every aspect of our lives over to a bunch of twentysomethings who were highly intelligent and capable but still couldn’t know how painful it could feel to give up control over my own life. If I needed something at the store, I had to ask someone to get it for me. If I wanted to speak to Barack, I usually had to send a request through one of his young staffers. Events and activities I didn’t know about would sometimes show up on my calendar.

But slowly, as a matter of survival, we were learning to live our lives more publicly, accepting the reality for what it was.

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