"You have to dig deep, but there was some stuff that was right there for me," Janet said during an appearance on "The Tonight Show with Jay Leno" on Thursday.
In one scene, Janet's character unleashes and smashes a table, something she said she was able to do by using her real world pain.
"Stuff that had just happened with my brother passing and also relationships," she continued. "Experiencing… exactly that."
As for opening herself up so emotionally and committing to the role, Janet said she threw caution into the wind and put her trust in director and writer Tyler Perry.
"You just have to trust and give it up, just let go and be very, very open," she told Jay.
"Why Did I Get Married Too?" opens in theaters on April 2.
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