Mischa, 33, was the one to pull the plug on their relationship.
"She broke it off with him a couple of weeks ago, and is just really taking time to be single right now," a source told RadarOnline.com.
The source continued, "James just turned out to be not the person that she thought he was!”
The actress has been laying low and working on herself since the breakup.
"Mischa is just taking some time to focus on herself right now. She hasn’t been doing a ton of promotion for the show like the rest of the cast has. She has adjusted to the show and to the cast, but there is just a lot of tension in her life and he was a big part of that," the insider explained.
James is an Australian model whose family is worth an estimated $574 million, according to the AFR Rich List. He first confirmed their romance back in June 2017.
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