How have the writers' attitude changed towards humans who leave the Doctor to pursue their own lives? Does it seem that the Classic show supported the idea that human companions made the better choice in pursuing their own paths? Did it seem more in the Classic show that the Doctor approved of this, especially if he thought a companion was becoming too attached? Is it the writers or the fans who give the impression that a departure like Martha's or even Sarah Jane represents rejection or settling for a second-best life?
(Thanks to viomisehunt for this week's topic! Have an idea for a topic, too? Submit it here!)