Gamophobia
Rather than a phobia, such behavior is linked to a number of personality disorders and neuroses. The majority of phobias are socially created, and are not found in any DSM Psychology manual. The inability to allow oneself to  be vulnerable and show their 'bad parts' has a personality disorder. When the individual displays reaction formation (love to hate) this is a neurotic defense mechanism. This can also be known as commitment phobia.