Just two days after the 38-year-old actress was photographed holding hands and packing on the PDA with Jamie Foxx (confirming their long-rumored romance!), she was spotted again on Thursday, all smiles while strutting the streets of New York City.
A source close to the brunette beauty tells ET that she now refers to herself and Foxx as "we."
"They send each other voice memos, instead of text messages," the source says, noting that the two were in constant contact while Holmes was out and about in the Big Apple. "She was talking about him all day and gushing about how much fun she has with him."
A lot has changed for Holmes over the years. The typically low-key mother of one "used to attend things as an obligation," the source says, but appears to be having a lot more fun now.
"She'd do what she was responsible to do and then she'd leave. She was a homebody," the source explains. "It's great to see her out and having fun, and I bet Jamie has played a big part in that."
Before dating Foxx, Holmes was married to Tom Cruise for five years before calling it quits in 2012. They share one child together, 11-year-old daughter Suri.
"She stepped out of the spotlight to focus on her family and more indie projects like Broadway and small TV and movie roles," the source says. "She kept her circle really tight, but it's been years since the divorce and Katie deserves to be happy. She doesn't seem to care anymore who knows what's going on with her and Jamie. She's letting down her guard and being more open."
And a lot of people are noticing the sudden change!
"We could not keep up with her," one of the photographers who recently snapped pics of Holmes in New York tells ET. "She was on every list for every party in New York! This is definitely out of character for her. She wasn't hiding from us or anything, she was strutting! She seemed like she was in a good mood."
Holmes appears to be having a blast during her trip to the city, completely slaying the fashion game. On Thursday, the Toledo, Ohio, native rocked four chic looks as part of New York Fashion Week.
She kicked off the day at the Adam Dalton Blake, Tiffany Huang, Ghazaleh Khalifeh fashion show, stepping out in a floral halter dress that highlighted her toned figure.
Later in the afternoon, Holmes opted for a more casual look, consisting of a baggy sweater, distressed denim jeans and leather boots.
She turned heads again a few hours later in a sexy emerald green dress with pointed-toe heels. Her berry pout was the perfect finishing touch!
Holmes' last look was a mix of cool and casual. She paired a black-and-white jacket with a denim jumpsuit and stilettos for the US Open Tennis Championships.