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"I'm not crazy," Demi Lovato says during her guest starring appearance on "Grey's Anatomy" next week. Demi plays a troubled teenage patient whose parents brought her in to Seattle Grace for schizophrenia. She will fall under the care of Karev.

Also in the episode airing May 13, an elderly patient admitted into the E.R. for a heart condition sees a familiar face, a long lost love who happens to be in the E.R. as well for a fractured arm, and the staff find themselves caught up in their love story. Meredith can't help but tell Cristina about her suspicions of Owen - which inevitably messes with Cristina's head.

In fact, Cristina is not the only one dealing with men. Teddy walks in to find Reed on Mark's bed while Bailey sees her man flirting with another staff in front of her eyes.

On a side note, Ellen Pompeo aka Meredith says she's not going to stay on the show long. "I haven't said I'm moving on," she told Extra. "I said that when my contract is up after Season 8 [in two years], I would probably not renew. I think the world has had a lot of Meredith Grey." There's no comment yet from ABC regarding this.