Sheryl Crow: 'The Best I've Felt in Years'

Sheryl Crow is one of those celebrities who seem much the same onstage and off.

Many fans see the rocker from Kennett, Miss., as a down-to-earth girlfriend who's easy to relate to.

Many more women can relate to the 44-year-old now that she's a breast cancer survivor.

Crow told Diane Sawyer in an exclusive interview with "Good Morning America" that she's fully recovered and feeling great. "I actually feel the best I've felt in years," she said.

Crow was diagnosed with cancer in her left breast in February. It was a total surprise. She isn't a smoker and doesn't have a history of breast cancer in her family.

Luckily, the cancer hadn't spread to her lymph nodes. The singer underwent a lumpectomy and a course of radiation that wiped out the cancer.

"Radiation was all that was required. It was seven weeks, five days a week, and not kind of a long process. You'd go in -- and literally eight [minutes] or 10 minutes long," Crow said.

"But over a course of seven weeks, you become fatigued and the breast becomes tougher and more painful and looks sunburned. And mostly what I experienced was fatigue."

Friends, Fish and 'American Idol'

In many ways, Crow was lucky. Weeks before, she and her boyfriend of two years, cyclist Lance Armstrong, had announced their separation.

"I was tired a lot," she said. "And also I was going through, you know, obviously, the trauma that I was going through before I was diagnosed. And so, all of it culminated at the same time and really forced me to just work my way through all of it."

Crow said she talked to Dana Reeve, who died of lung cancer in March, and she told her the only way to go through grief was to grieve.

"And so. … That's just kind of what I did. I mean, I just sat with it and just worked my way through it."

She meditated and changed her diet.

"I kind of went into a full-on Eskimo diet, where I ate a lot of salmon. In fact, I'm salmoned out of my brains, but just really eating a lot of omega-six, instead of omega-three, and really green vegetables, just eating really clean, organic food. … Listen, I haven't had a doughnut in I can't remember when."

Crow surrounded herself with her parents; a group of women, including Courtney Cox, Laura Dern and Jennifer Aniston; and others.

"I had this incredible tribe of women just descend upon me and carry me through the whole experience on their backs," she said. "And also my family took shifts coming out."

For the first time in a long time, she sat around and watched TV, including "American Idol."

"You know, I was rooting for Elliott [Yamin] the whole way," she said, with a laugh. "I'm still mad as a hornet he didn't win."

Wants Kids Soon

Her first concert back a few weeks ago was not just a performance for her old fans.

"I have so many people walk up to me who are just so much younger than me that say, 'I survived breast cancer' or 'I'm battling breast cancer, and it's all around us,'" Crow said.

She tells other women to be vigilant about getting mammograms and self-examinations.

"It's all about early detection, to find out what your family history is, because if you are 26 and you have it in your family, it will matter, so get a base-line mammogram and just follow it every year," she said.

What might this rock star, celebrity and survivor say to the Sheryl Crow just starting out, before the hit records and high-profile relationship?

"Try to at least address my fears and not be overcome by that," she said. "[The] fear of things not always working out. You come to a point in your life where you realize it's not my job to prove to my parents or to my record label or to the world or to my lover that I matter. The fact is is that you matter."

"It's not a good place to be concerned with always being right with everybody, always pleasing people, because ultimately you wind up betraying yourself a lot."

As for the future, Crow said she was looking forward to having kids at some point, finding a strong relationship, and continuing to make music.

"I do think I'll have kids. [Whether] … I adopt or whether it's my own, I really have a strong feeling that I will. And I think it will [be] sooner than later," she said. "And the idea of marriage, I love that idea. But I think what I love more is just being with somebody who really creates space for you and gets you."

Crow said she wanted to hang on to her newfound wisdom.

"I think I'm like all new cancer survivors," she said. "You fear that this heightened awareness is going to go away and that you're going to forget everything and you're just going to go back to the loser you were before or whatever, you know."

"And what I've realized is that all these experiences are deepening experiences. And they are -- they are the moments where obstacles are removed and opportunities come in."