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Life is no longer all about Los Angeles for Khloe Kardashian, now that things are getting serious with Cleveland Cavaliers star Tristan Thompson.

The new couple -- who were first spotted openly flirting before and during Memorial Day weekend -- have said "I love you," a source tells Us Weekly.

"She's so into him and he's really into her," gushes the insider. And with Tristan based in Cleveland for his NBA responsibilities, Khloe's been making the Midwestern city her home away from home.

Us Weekly's source says "Khloé is very comfortable and happy there," a fact she's made clear with multiple trips to Cleveland during which she's been spotted hanging out with Tristan and his friends, celebrating his team's wins and most recently catching a Cleveland Browns game with her man.

"She wants to be there with him," says the insider.

Even the recent news Tristan's expecting a baby with his ex, Jordy C, seems not to have phased Khloe, perhaps because she's no stranger to relationships that continue past the end of the romance. Khloe first filed for divorce from Lamar Odom in 2013, but it wasn't until October 2016 that the marriage legally ended, with Khloe floating the idea that she wanted the freedom to potentially remarry and start a family at some point.

As for Tristan, "Khloé's supporting him," says the source. "They're very serious."

They also seem to have similar ideas about what constitutes quality time together.

While promoting her new Good American denim collection in Los Angeles in October, the reality star opened up about what she and Tristan like to do together during their downtime.

"I'm a homebody, so for me it's just, like, chill and watching TV and having a drink. It's like intimate one-on-one time. … I'm more of an at-home person," she told Us Weekly.

"[We like to] just chill at home. That's really what we do, mellow. We're not that exciting. I feel like people think I'm, like, wild and, like, hanging from chandeliers."

In October, it was reported Khloe and Tristan had become exclusive.