The model is said to have called time on their relationship last week after Thom grew jealous of her recent regular meetings with ex-boyfriend Danny Cipriani.
Speaking to The Sun, a source said, "She's never stopped loving Danny.
"Even though there was nothing going on while she and Thom were together, Thom hated the fact she was seeing him and Kelly refused to end their meetings.
"After one row too many the pair decided to end things. She's been leaning on Danny since the break-up and, while she's devastated, she knows it's for the best."
Thom Evans has reportedly moved out of their shared flat in Los Angeles, where he is attempting to launch an acting career.
The source added, "Thom told Kelly that he's always wanted to live in LA but never made the leap because she was so against it.
"He's booked loads of auditions. It's also easier for her to have this distance right now as it's all so raw."
Kelly tweeted about the split explaining all to her fans.
Thom and I mutually agreed to go our separate ways some time ago. It had absolutely nothing to do with a third party.— Kelly Brook (@IAMKELLYBROOK) February 1, 2013
Kelly Brook began dating Thom Evans in November 2010 and Kelly suffered a miscarriage with their child the following May.
She dated Danny Cipriani for two years before splitting up in 2010.
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