This is a clip from 1960’s ‘Doctor Who’ from the end of a serial called ‘The Dalek Invasion of Earth’.
It shows The Doctor played by an old man (William Hartnell) saying goodbye to his companion and grandaughter Susan Foreman (played by Carole Ann Ford). Susan is unwillingly staying with a person called David Campbell to spend the rest of her life with him and to probably get married and have kids with him.
The Doctor doesn’t want her going around with a ‘silly old buffer’ like him anymore as she’s a grown woman now and shouldn’t be looking after him, she should be looking after herself and David should be looking after her.
Nowadays in the modern episodes, The Doctor doesn’t let companions go just like that so quickly as he gets lonely, but that was his grandaughter and he was an old man in that body so he obviously felt different back then.
Also the modern episodes are set after the time war and the 1960’s episodes are set before the time war. This means before it all of his race of time lords were alive so he wasn’t so lonely, but after it all of his race of time lords are dead so he’s bound to react differently in different situations and that is why he is more lonely in the modern episodes.
Also the fact that he is half human and half time lord too make him similar to us in some respect with the emotions he experiences.
For more information on this subject see my other blog post: ‘How science-fiction has changed over the years’.