She knows how it looked from the outside, as she says, "the beautiful family, the superstar husband," Will Smith, "the lavish lifestyle." But, Smith says, she'd "put on a brave face for two decades." She was battling severe depression.

In her new book Worthy, Smith, 52, tells her journey not just from the streets of Baltimore to the heights of Hollywood, but of her struggles.

She writes of surviving parents with substance abuse issues, succeeding in entertainment and, most importantly, finding herself worth not just all the hard work but the love of herself.

Her journey to "reclamation," as she puts it, began when hitting a mental health bottom, a chance encounter in her kitchen, and getting help from a surprising source.

Read on for an excerpt from her book, out Oct. 17, which describes the start of her journey out of darkness.

I’ve pulled off the curving mountain road onto what turns out to be the top of a steep driveway leading down to the house of the Medicine Woman — whom I just met on the phone only a couple of weeks earlier. I’m sitting and staring down the driveway, between a thick overhang of foliage, on a beautiful clear night that should feel magical but instead feels full of dread.

I take a couple of deep breaths, trying to calm myself. I feel crazy. My mind, which was so focused on getting me here, is now suddenly betraying me, leaving me to feel vulnerable in ways that I hate. In this moment I’m pounded by the same terrifying feelings I felt in past experiences when I put myself in situations that it’s a miracle I lived to tell.

The scariest aspect of those incidents was that whether I lived or died was in someone else’s hands. And that lack of control may explain how I’m feeling here, in my car at the top of this driveway, as I try to get my bearings. I want to be grateful for this moment, for this opportunity, but a feeling of helplessness floods me.

All I can think to do is pray with all my heart, as sincerely as possible. My hands press together. I try desperately to steady my mind.

Don’t be afraid, I tell myself. You are in peaceful, beautiful Ojai. Why are you so scared? Because, I answer right back, what if THIS actually kills me?

Three months earlier, in the wake of my fortieth birthday, my biggest worry was Well, what if it DOESN’T?

For two decades, I had been putting on a good face, going with the flow, telling everyone I was okay. Yet underneath, bouts of depression and overwhelming hopelessness had smoldered until they turned into raging hellfire in my broken heart. Unwelcome feelings — of not deserving love — made it harder to understand the disconnect between the so-called perfect life I had achieved and the well of loss I carried with me. Therapy helped up to a point. It got me to forty! But to what end?

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Jada Pinkett Smith

I would later be diagnosed and informed that I suffer from complex trauma with PTSD and dissociation, but without this guidepost, I was a chronic mess with no fix, no possibility to heal. Every morning, waking up was like walking the plank of doom — could I make it to four p.m.? If I could, I had survived the day. I always wanted to sleep, but I never slept well. My children could put a smile on my face and were my only motivation to keep me going, but more and more, I could feel myself losing my grip of connection to them.

With all of this, I was slammed by the reality that I’d been checking off boxes meant to define being enough to deserve “having it all.” What that meant to me was that I would be “enough” to be loved in a way that life didn’t hurt anymore. Those boxes I’d been checking had not delivered the gifts that had been promised. I followed the rules ... the rules we’re told to follow. You work hard, make sacrifices for those you love. The rules tell you: Be a doting mother and a doting wife, do the work required, and life turns into paradise. NOPE. A loving relationship, harmony, peace ... that happiness had yet to be delivered.

“On paper,” it all looked grand — I had the beautiful family, the superstar husband, the lavish lifestyle, fame and fortune. I had my own career, the freedom and support to pursue creative outlets. The sweetest part was my kids — Jaden, Willow, and my bonus son, Trey — my three favorite people in the world. They were, hands down, the best thing that ever happened to me. Yet none of that prevented me from hitting the wall I was speeding toward at a hundred miles per hour, knowing full well — this s---’s gonna blow!

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Trey Smith, Willow Smith, Jaden Smith, Will Smith and Jada Pinkett Smith

I had sought help everywhere you can imagine — from Goddess gatherings, silent yoga retreats, backpacking alone, studying every religion you can think of, you name it. I even went to Cuba and met with a Padrino (that was intense). None of it offered a lasting solution. Adding to my distress, Will and I weren’t in a good place and hadn’t been for a while. I couldn’t make it right no matter how hard I tried. We couldn’t hear or see each other — at all. Confiding in my close friends seemed unfair to them and to Will and me.

And so, by Thanksgiving, I’d fallen into despair and wanted to be on this earth less and less. This was not living.