On Jan. 10, Mary Matalin walked away from her job as Vice President Dick Cheney's top political adviser. A consummate political animal—a veteran campaigner and conservative talk show host so enamored of ideological battles that she married her opposite number, ex-Clinton aide James Carville—she told the world she wanted to focus on her family, Carville, 58, and daughters Matty, 7, and Emma, 4.

In her first detailed interview since stepping down, Matalin, 49, reveals how the stress of juggling marriage, motherhood and one of the world's most demanding jobs regularly reduced her—and her loved ones—to tears. "The kids pretty much play the hands they're dealt," says Carville, a Democratic consultant and Crossfire cohost. "But they like this hand better."

As a Republican consultant, Matalin still advises the White House. But now, with help from friends, family and part-time nannies, she does so from an Alexandria, Va., town-house, working on a few projects a month instead of 70 hours a week. She spoke there with correspondent Jane Sims Podesta as the girls went sledding nearby.

There was no single breaking point when I said, "I can't take this anymore." But eventually, it got so that I would drive to work and cry because I was so tired. I'd leave the house at 5:30 or 6 a.m. I could never see my kids in the morning, and I could never pick them up from school. Each hour you work at the White House is intense—the job takes over. Then you come home and start your other job, which is just as intense. I managed to pass the litmus test as a mother and marginally acceptable wife only because Dick Cheney and George Bush let me pick my projects and, when possible, set my schedule. Lynne Cheney told me early on, "Find your balance." The Cheneys are amazing that way. The Vice President will stop almost any meeting to take a call from his daughters or grandchildren. He always lights up.

I thought I'd stay for a year, then leave around Christmas 2001. But 9/11 changed everything. I was at the White House when the planes hit, when the Secret Service said, "You've got to evacuate," then literally picked the Vice President up while the rest of us ran to the parking lot. I wasn't scared. We didn't know a plane was heading toward the White House. All I was thinking about was my red patent leather high heels. I'm thinking, "Why didn't I bring my running shoes?"

For weeks after that we were in high 9/11 mode. Several times I went to "undisclosed locations" with Vice President Cheney. I'd call home and say, "I'm leaving. I don't know when I'll be coming back." Fortunately I had a wonderful nanny, Geneva Watkins. We were like sisters. But in mid-October 2001 I came home and she looked very tired. I gave her the week off. That Saturday she died of cancer, in her early 60s. I noticed she was slowing down, but she never told us it was cancer. I couldn't stop crying for an hour. All Emma wanted was to go to heaven to be with her. She refused to go to school—she'd have fits. So until spring 2002, I brought Emma to work. She'd sit in my office and watch Dragon Tales.

I've never liked being far away from the girls, in case something bad happens. So our 10-day trip to the Mideast in March 2002 frightened me. The first time I called to check on the kids I was told both their hamsters were dead. And I got blamed: "Mommy, you left them in the windows. Everybody knows hamsters overheat." Then I called from Jerusalem. We had spent the night writing the statement that Vice President Cheney would conditionally agree to meet with Arafat; at dawn we were supposed to go over strategy. That night Matty tells me she's about to lose her first tooth, so I'm on the phone till 2 a.m. "Put a wet rag on it. Tease it. Spit it out."

This saga went on all week. James went to Matty's school fair and, unlike us, some parents had clearly helped their kids with their career projects. Hers was about being a teacher; she'd brought an apple, a blackboard and a ruler. James calls me in tears: "You should have seen the fire stations and villages." He thought he'd let Matty down. I'm hearing this in Oman. We're in this great hotel watching a beautiful sunset, and he's having this crying attack. That was the only time I really felt, "What am I doing here?"

Since leaving the White House, I feel that I'm finally nurturing our marriage. We never talk politics—I believe what I believe and I think he is utterly, totally, completely wrong. But we agree about everything else. We run and work out together, we're food snobs, wine snobs. Recently we went to pick out cabinets, and then I went back and spent a half hour looking at knobs. I told James last night, "I'm in nirvana."

I'm always asked why men don't have to take time out to stay home with their children. I don't care if it's a double standard. Motherhood is an incredibly unique female experience. I loved being pregnant, I loved breast-feeding. Every age is such an unexpected joy. Now I can get Matty dressed in the morning and drive her to school. Then I come home and take Emma. We put the car stereo on super loud and sing Britney Spears. I'm very in their face—"pick it up, bring your dish to the sink"—but I like hanging out with them. We go to the movies. We do homework and crafts. They just like me to be here.