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Oh, J-Lo. In her new video for "Dance Again," she drapes herself over 24-year-old back up dancer Casper Smart in the same way other 40-somethings might caress a Porsche, or a five-figure handbag, or their dermatologist's botox hand.

It appears that Jenny From the Block's looking at the clock. At 42, the mom of two seems to be in the throes of a mid-life crisis. Perhaps she needs a road map. Here's how her Hollywood colleagues have handled theirs:

- Demi Moore married Ashton Kutcher. She was 42, he was 27. Fast forward six years, they're getting divorced, she's having a breakdown, and he's partying with Brazilian models south of the border. So the 42-year-old marries 20-something boy toy thing has its drawbacks.

- Madonna ditched Guy Ritchie. The Material Girl said sayonara to her second husband in 2008, the year she hit the big 5-0, and channeled her frustrations from their nearly 8-year-long union into her latest album, "MDNA." In "I Don't Give A …," she sings, "I tried to be a good girl/I tried to be your wife/Diminished myself/And I swallowed my light/I tried to become all/That you expect of me/And if it was a failure/I don't give a [expletive]." Although since she's now linked to Brahim Zaibat, a 24-year-old back up dancer who's closer to her daughter's age than her own, she may not be the best example for J-Lo to follow.

- Susan Sarandon took up ping-pong. This seems like the healthiest option of all. After splitting from longtime partner Tim Robbins in 2009, Sarandon, 65, threw herself into Spin, a ping-pong nightclub that started in New York City and now has locations all over the country. She brushed off rumors that she was dating her 30-something business partner, Jonathan Bricklin, like a bad serve. "I'm just so busy at my club that I really haven't had time for romance," she told USA Today in 2010.