<P> Derek regrets his decision to return to his wife and Meredith must decide whether to continue a relationship with Finn, or allow Derek a second chance . </P> <P> When Ellis experiences a rare, completely lucid day, and expresses her immense disappointment at how ordinary Meredith has turned out to be, she becomes depressed and possibly suicidal . During a ferryboat accident, Meredith is knocked into the water and chooses to give up and drown, rather than fight and swim . She flatlines at the hospital, and awakens in an "afterlife", where she interacts with deceased former acquaintances . Ellis dies in the interim, and Meredith meets with her mother, who tells her that she is anything but ordinary . She is subsequently resuscitated at the insistence of Cristina . Derek distances himself from Meredith as the result of her self recklessness, prompting her to seek therapy to address her problems . Meredith sees a therapist, Dr. Wyatt (Amy Madigan), to seek happiness and begins to successfully tackle her issues . Meredith found her mother's diaries, dredging up old memories and secrets for her to work through . Meanwhile, Meredith nearly fails her intern exam after a drunken Thatcher publicly blames Meredith for the death of his wife, Susan, a distraught Grey sits through her entire test without writing a single answer . Dr. Webber gives her a second chance, saving her from destroying her career . </P> <P> After Meredith is promoted to a resident, her younger half - sister Lexie Grey (Chyler Leigh) begins working at Seattle Grace as an intern . Meredith initially rejects Lexie's attempts to form a relationship, but slowly softens towards her . The sisters are very different people with different childhoods . Lexie had an idealistic family life and often has difficulty understanding her much darker sister, who does not have the same positive associations with family as Lexie . </P> <P> She later initiates a neurosurgical clinical trial, enlisting Derek as a consulting neurosurgeon . The trial fails repeatedly, but the final patient they treat survives, which leads them to reuniting and moving in together . Their relationship is healthier than before, but still experiences snags as the two attempt to understand each other and navigate what they now look on as a permanent, long - term relationship . Meredith relies heavily on Cristina for emotional support and guidance . Eventually, Derek and Meredith decide to marry, but on their wedding day, the pair give their "perfect" wedding ceremony to Izzie and Alex, to marry each other during the planned ceremony instead . </P>

Who does meredith grey marry after derek dies