Recently I was dining with a friend who, like me, works in the media. She is in her mid-40s and realizes that her days on the air are numbered. Putting aside the issue of why it's acceptable for men in their 70s to be on the air but women over 50 are considered too old, she was grasping for ideas on how to reinvent herself so as to stay employed for another two decades.

She has reached success, but it's ephemeral. She no sooner reached the top of her game than the game she was playing shut down. Nearly every week now she and I hear of someone in our field who's moving on, retiring, or being forced to take a buyout.

My friend is in what author and Texas entrepreneur Bob Buford calls "halftime"—that period in your life when you switch from what you've done for the past 20 years to what you will do for the rest of your life. Call it self-renewal or the next big thing or refocusing. You begin asking what you want to be remembered for and what your epitaph would be. You think of all the things about your life that dissatisfy you and that, if you're going to change them, you must do it now.

When I decided I wanted a child and that I would do whatever I had to do to get one, I spent my 47th birthday talking with a local adoption agency. Jobs don't last, I figured, but people do. Three years later, I became a mom—one of the better decisions I've ever made.

A friend of mine decided to take a chance on a thrice-divorced—and repentant—man, and got married for the first time at age 54. She is as happy as a clam.

Famed rescuer Corrie Ten Boom was age 50 in 1942, the year her family became involved in the Dutch resistance and began hiding Jews in their Haarlem home. She spent most of her 54th year in the Ravensbruck concentration camp, and in the years after that became known for her helpful advice on forgiveness. She was 79 when her most famous book, The Hiding Place, was published in 1971.

So, good things do happen in one's second half, especially since 70 has become the new 50.

Buford's Halftime and Beyond Halftime are aimed mostly at men who have made their fortunes in the first half of their lives, done the wife-and-kids bit, and are ready to lead lives that are about meaning more than money. Some are only in their 40s when they realize they are nearing burnout. Others are forced into retirement by their 60s, he says, with at least 20 good years ahead of them. That's the time to mentor, advise, and train like-minded acolytes among the young.

Many women do not have the luxury of dialing up life's second half while living off the proceeds of the first. They have long since hit the glass ceiling, never getting to the point where they can retire on their savings. Others have spent a lifetime invested in their families and are in no shape to compete in today's shrunken workplace.

As my friend and I talked, she admitted that she has little interest for anything else besides journalism. She is having to dig deep within herself to find wellsprings of other dreams—buried for decades but now worth examining—of what else she loves to do. She has to listen to what her heart wants.

And while she's still employed, she must develop a parallel career so that when she does make the jump, the foundation is laid. People ask me how I find the time to write books while working full-time as a journalist, serving seven years on the board of a journalists group, and in recent years, mothering a small child. I find the time because I have to; in these uncertain times, we all need alternate options and revenue streams: whether we are cleaning homes, baking cupcakes, or otherwise freelancing our wares.

I would be interested in hearing from other women who have taken action to change their lives at the mid-point. What did you do and how did you afford it?

It's quite clear that the current economic downturn means major decisions for most of us somewhere down the line. Lent, the season of introspection, fasting, and repentance, begins in less than a month (Feb. 17); it's an ideal time to ask God whether to take that less-traveled path. Setting some time apart has, in the past, helped me to gauge what may be coming my way not only in the immediate future, but also in the next 10 years. It's very difficult to make major life changes without at least some time alone to ponder and pray. For this, the silence of mid-winter is ideal.