Y’all don’t get it:
They’re entirely different characters with the same names and played by the same and different actors.
You see, “the show” completely changes whenever there is a different script writer or director or producer or weather conditions or actor’s health status that day.
So when you see what you think of as:
YOUR CHARACTER
behaving strangely, that’s because you’re thinking of that OTHER CHARACTER that you saw that had the same NAME but was played by the same or different actor or actress in a story written by the same or different script writer and along with all of the other parameters, renders it a COMPMLETELY DIFFERENT character every single “episode”.
Acceptance of “episode singularity” is the best thing you can do for your Doctor Who mental health.