"Kristen falls so easily and she is really into Sara," a source told RadarOnline.com of the Twilight star. "But her model ex (Maxwell) told everyone that Sara is a rebound and contacted Sara to let her know that Kristen is only using her."
In response, an angry Stewart, "flipped out on Stella and told her to leave her and her life alone."
As RadarOnline.com readers know, Stewart, 28, dumped longtime girlfriend Maxwell, also 28, at the end of last year, after the Victoria's Secret model became "obsessed with fame" and was accused of taking advantage of the Still Alice star.
Less than a week after their split, Stewart was spotted packing on PDA all over L.A. with stylist Dinkin.
"Stella f****d it up, not Kristen," the source revealed. "Kristen wanted something real with someone low key and Sara doesn't care about the spotlight. She treats Kristen like a normal person, just as she is."
During an appearance on Saturday Night Live in 2017, Stewart described herself as, "so gay," later clarifying that she was bisexual and still open to dating men.
But she was with Maxwell from 2016 until they split at the end of 2018.
Watching Stewart move on so quickly has greatly affected Maxwell, especially since, as RadarOnline.com reported, the bickering ladies made a pact not to rub it in each other's faces by dating anyone else publicly for a while.
"But Kristen couldn't help herself and decided to go public with Sara almost right away," another insider snitched.
Stewart and Dinkin have only grown closer since then. The two even spent the holiday season together, further cementing their love.
An insider said they are already discussing taking the next big step.
"Kristen and Sara are already talking about moving in together," the source revealed.
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