In early 2000, Michelle broke off a near engagement to a Muslim boyfriend, citing opposition to religious requests he made of her. She has since been linked with her Fast and the Furious co-star Vin Diesel and S.W.A.T. co-star Olivier Martinez. In 2006, Michelle told Cosmopolitan magazine that she is not a lesbian, but had "experimented with both sexes." Later that year, her openly bisexual Bloodrayne co-star Kristanna Loken made comments to The Advocate hinting the two were in a relationship, although the relationship was never confirmed. In 2007, the lesbian magazine Curve ran a cover story that claimed Michelle to be bisexual. Michelle criticized the magazine for this, asserting that the magazine, stating that she wasn't a lesbian.
In early 2014, Michelle and Cara started dating. They were introduced in the States through mutual friends and have been dividing their time between London and California. The first indication in the media that they were dating was during a public showcase of affection during a New York Knicks' game. Since, the happy couple has been seen doing everything together from tuk tuk racing and hanging out at London Zoo to getting vitamin drips. They have publicly admitted to dating in February, 2014 and said to have the blessings of their respective families.