Kuriansky said the actress has an uphill battle.
"Seeking full custody is a huge move," she said. "Legally and emotionally, you have to have a lot of strength to go up against Tom Cruise, the movie star."
But Holmes has marshalled her forces, including adding a second divorce attorney, Allan E. Mayefsky, who represented model Christie Brinkley in her divorces. And she also has her father, who is a divorce attorney in Ohio.
Holmes may have been planning the split for some time. She reportedly spent much of her time in the past year in New York and obtained her own apartment in the Chelsea neighborhood in the past month.
While Holmes likely gains public sympathy with the reports that she may be divorcing out of a desire to protect her daughter, Kuriansky believes the split could also been driven by the actress's own needs.
"She started out with this fantasy of him, her dream as a little girl of marrying Tom Cruise, but the bubble has been burst," said Kuriansky, author of "The Complete Idiot's Guide to Healthy Relationships."
"This is about her as a mom, a wife, an actress and a woman stepping into her own," Kuriansky said.