Trouble in paradise?

Katie Holmes and Jamie Foxx have been together since 2013, but apparently Jamie's longtime girlfriend wasn't on his mind during the Fourth of July.

A source — who attended the Red, White, and Bootsy Party on Tuesday, July 4 — told In Touch, “He literally ran directly to a slender brunette and started dancing and flirting with her, they were both smiling from ear to ear." The source added, "Jamie seemed like such a charmer and ladies’ man. He was ready to party and didn’t seem to care who saw him.”

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Yet the Django Unchained actor's behavior isn't anything new.

“When Jamie is out, Katie becomes an afterthought,” a friend said of the couple. “He used to be subtle when it came to other women, but not anymore. He acts like a single frat boy.”

Katie — who arrived in Montreal with daughter Suri, 11 (two days before Jamie was seen getting cozy with the mystery woman), “is very much in love with Jamie and wants to marry again one day,” the source said. “But Jamie treats her like a booty call. He just won’t commit.”

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💕💕💕💕

A post shared by Katie Holmes (@katieholmes212) on

In fact, Jamie won’t even admit they’re dating. During a trip to Disneyland on Monday, July 3, he laughed and remained silent when asked if the pair were together.

“When they first started dating, there was this excitement because their relationship was a secret and felt forbidden,” said a source.

A second source added that they would often meet late at night or early in the morning so they wouldn’t be seen. "They also spent many romantic nights together on yachts because they felt safe to be alone there," the source said.

Said the first source, “Their relationship was so passionate, but his intention was never to settle down.”

Although Katie's friends are concerned, the Dawson’s Creek alum, 38, appears happy — at least on the outside.

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Happy Sunday! #setlife #thegift

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Over the weekend, Katie posted a sweet snap on Instagram with the caption, "Happy Sunday!" using the hashtags "#setlife" and "#thegift."

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The Katie insider concluded, “She knows what’s going on, but she loves Jamie and will take things how they are over ending the relationship for good.”