<P> Due to having severe PTSD and being unable to do her job correctly anymore, Cristina quits and begins bartending and eventually throws a housewarming party . Derek helps Cristina emotionally and she ultimately decides to go to work after helping the victim of a school shooting . Yang discovers she is pregnant with Hunt's child, and decides to get an abortion . Though Hunt accompanies her to the abortion, he is extremely angry with her decision . Yang then operates on Henry Burton (Scott Foley), Altman's husband, unknown of his identity . When the surgery fails and he dies, Yang is guilt stricken upon learning of her patient's identity . Altman forgives Yang and forces Yang to realize that she did everything possible . Altman's mentorship of Yang is punishing at times, and Altman brutally emphasizes that Yang must learn patience, compassion, and the basics over the flashy surgeries Yang prefers . Altman's tutelage is successful, and Yang evolves into an aware and well - rounded surgeon because of it . Altman allows Yang to come up with a wish list of dream surgeries to fulfill before Altman resigns and moves on . </P> <P> Yang and Hunt distance themselves from each other as they keep fighting over the abortion, despite attending marriage counselling . Hunt has a one - night stand with a patient's friend, leaving Yang heartbroken . She decides to move on, unsure of her future with him . As the end of the fifth year of residency is near, the surgical residents, including Yang, prepare for their medical boards and for the different fellowships they plan on joining . After she passes her exams, Yang reconciles with Hunt and tells him she is leaving Seattle for the Mayo Clinic, Minnesota . Afterward, Yang, Meredith, Shepherd, Arizona Robbins (Jessica Capshaw), Mark Sloan (Eric Dane), and Lexie Grey (Chyler Leigh) are involved in an aviation accident while on the way to Boise, Idaho to perform surgery on conjoined twins . Lexie dies, and Mark later succumbs to his injuries after they are rescued and dies . Following their rescue, Yang, traumatized, suffers from brief reactive psychosis which provokes violent outbursts and makes her unresponsive . Yang leaves Seattle to become a cardiothoracic surgical fellow and goes, as planned, to the Mayo Clinic, but has difficulties adapting to her new colleagues' way of working . While in Minnesota, Yang develops a friendship with a near - retirement cardio surgeon, Craig Thomas (William Daniels). She mainly teases him with comments regarding his old age . She also begins an affair with the head of surgery Dr. Parker (Steven Culp) who has issues with Thomas . After Thomas dies from a heart attack, Yang returns to Seattle . </P> <P> Cristina is re-hired and Owen asks for a divorce once Cristina wants to reconcile . Shocked, Cristina agrees, but later finds out that the potential conflict of interest regarding the plane crash lawsuit was a key motive behind Owen's request and confronts him . Owen tells her that he' feels responsible' and was worried as he thought she was dead . They have a sexual relationship after divorcing . The hospital is sued and found guilty of negligence . The surviving doctors, including Yang, must receive $15 million of compensation each, which leads the hospital to a near bankruptcy as the insurers refuse to pay . Yang, Callie Torres (Sara Ramirez), and the other surviving doctors buy the hospital with the help of the Harper - Avery Foundation to prevent it from closing, and each become members of the new directing board . After buying the hospital, Yang realizes that she was made for the O.R. and breaks things off with Owen because he still wants kids and she still doesn't . </P> <P> After breaking up with Owen, Cristina continues to excel at surgery and becomes de facto chief of cardio . Although supportive of Meredith's choice to become a mother, Cristina points out the fact that it has hurt Meredith's career and clinical judgement . This causes a wedge in their friendship . Grey attempts to catch up professionally with a research trial, but the divide widens when Cristina's trial overshadows Grey's and steals Grey's resources . When Dr. Shane Ross, a second - year resident, stands up to Meredith for her, Cristina gives Shane a kiss . Later, she begins sleeping with him, as well as becoming his mentor and passing on the skills learned from Altman . Cristina's project is immensely successful and she is informed that she could be considered for the Harper Avery award from her 3 - D printing of a heart conduit . Grey and Yang reconcile when Grey acknowledges that Yang is correct, she has surpassed Grey, and that Grey is jealous of Yang's professional freedom and success, while her own is hampered by her family . </P>

What episode do cristina and owen break up
find me the text answering this question