When the amnesiac Doctor falls in love in the `` Human Nature '' \ / `` The Family of Blood '' two-parter , a pained Martha claims `` You had to go and fall in love with a human ... and it was n't me '' .
Nevertheless , she becomes frustrated because the Doctor does not realize her feelings for him , When the Doctor falls in love ( while believing himself to be a human ) in the `` Human Nature '' \ / `` The Family of Blood '' two-parter , a pained Martha claims `` You had to go and fall in love with a human ... and it was n't me '' .