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Christina Applegate

She has an "angel" of a boyfriend, Dutch bass player Martyn Lenoble, who "loves me from head to toe." She has a cozy Malibu beach house that she calls "the best thing I've ever done for myself." And, after a very public battle with breast cancer that has given her a gratifying "feeling of purpose," she has a new lease on life. Last March Christina Applegate, 37, was diagnosed with a disease that her mother, Nancy Priddy, has battled—and by July the actress opted to undergo a double mastectomy. But within weeks Applegate presented an award at the Emmys in a stunning Reem Acra gown and returned to the set of her ABC sitcom, Samantha Who? "You have to get through the physical transformations, then buck up, go to work and try to be the normal, happy Christina for everyone around you," says Applegate, who had reconstructive breast surgery last November. In an extensive interview the star—now cancer-free—sat down with PEOPLE's Elizabeth Leonard to share her journey and revel in the beauty of living each day to the fullest.

What's your favorite personality trait?
My sense of humor. I like laughing and making people laugh—not just on set, but in life. I used to be really shy, but I started to come into my own in my late 20s and early 30s. Now I'm not afraid to speak up in a room full of people and be a part of the conversation.

What feature do you get the most compliments on?
My eyes and my eye color, which completely changes depending on what environment I'm in. My driver's license says "hazel green" since that's what my mother always told me they were. But they have brown and gold and green in them, and they change colors.

What's your beauty hang-up?
I have short legs and it drives me crazy! I've got a really long torso and short legs. I can pull it off with the right jeans, but it's taken time to figure that out. There are people, like Cameron Diaz, who have incredibly long legs and you go, "Wow, how can you ever have a problem if you just wake up with long legs?!" I'd love to wake up to them one day, but it's just not going to happen!

Can you tell us about your boyfriend?
He's been a friend for about 13 years. [They began dating last May.] Our relationship gets stronger and stronger. I'm really lucky.

You and actor Johnathon Schaech finalized your divorce in 2007. Would you get married again?
Absolutely. You go into relationships hoping they'll last forever, so that's the hope. I was always looking for what my perfect type was, and I never really found it until now. He's an angel.

What about kids?
Absolutely. I mean I can't keep babying just these furry creatures [Tallulah, a miniature pinscher/dachshund mix, and her cat Bella] for the rest of my life!

How did you react when you first learned about your cancer diagnosis?
It's a roller coaster of emotions. But there was a calm about what I had to do. I watched my mom go through cancer [both breast cancer, at age 38, and ovarian-related cancer, at age 54] and so I know how this works. I got macrobiotic chefs, and I wouldn't let stress in my home in any way, shape or form. I really tried to take everything in stride and one day at a time.

Why did you decide to have a double mastectomy?
When they found out that I had the BRCA1 mutation [a gene that increases the risk of developing breast and ovarian cancers], I had to make the decision. If you have the gene, they tell you your chances are 80 percent that [the cancer] will come back. So I was like, "Uh, where's the decision to be made? Obviously, let's go." My mom had a mastectomy when she was 38, so she totally gets it.

Now that you've had reconstructive breast surgery, how do you feel when you see yourself naked?
It's hard. You don't look the same anymore and you never will. A part of you is gone. None of the women I know [who have undergone similar surgery] are like, "Yay, I love my boobs!" But you have to embrace them. It's a decision that you made to save your life.

How does your boyfriend make you feel about your new body?
Beautiful. He doesn't even see it.

What's the most awkward side effect of having reconstructive surgery?
The numbness is strange. I can't feel anything. I don't know if they're hanging out in clothes, so I need someone to make sure they're under wraps.

Are there any positive aspects?
I don't have to wear a bra! They don't hang down to my knees like they did before. They hang up there. They're pretty solid. They're not going anywhere. And the gals look good in tank tops, and they didn't before.

You recovered from your surgery in your new Malibu beach house ...
I've always dreamt of one, but I always thought, "Well, that's just too expensive, blah blah blah." After the diagnosis, I was like, "What am I waiting for?" It's the best thing I've ever done for myself. I love walking on the beach and looking for sea glass. I can do it for hours and hours.

After everything you've been through, do you feel brave, lucky or unlucky?
I think it's okay to feel all of the above. Some days you can't be brave. Sometimes you feel lucky because you've been given this chance to change your life. There's a spectrum of emotions.

A paparazzo snapped a photo of you smoking recently and it caused a stir. How did that feel?
It's been very painful because I feel it was discounting all the work that I've done. The day I found out I had cancer I quit anything that was bad for me that I was putting in my body. Over the last year, with everything that's happened [including the death of her ex-boyfriend Lee Grivas in July], there have been a couple of times that I've slipped up. That was one of those rare occasions—and of course they got a picture.

Having made it through the toughest year of your life, do you feel gratitude?
I'm grateful that I'm through the thick of it, because that was really hard. And I'm grateful that I have been able to influence people in a good way, I hope, with all the work I've been trying to do to open people's eyes about the reality of this [see box on the foundation she started]. I'm very grateful to Martyn for coming along at the time that he did because he's been my rock through all of this. He gave me something to really want to live for and something to smile about.

How has this experience changed the way you view life?
When everything happened I felt a charge to make every day really, really important; and make every experience the best that it could possibly be; and to take as good care of myself as I could; and to give a lot of love. You've got to kind of go for joy and happiness as if your life depended on it and flush away anything that doesn't fit within that. That's not just for people who are cancer survivors. That should be for everybody.

Want more? Get exclusive video of Christina at PEOPLE.COM/MOSTBEAUTIFUL