I think a big part of the Doctor’s personality is that he always tries to do the right thing. They try to portray the Doctor as a person of good character. So why does he treat Mickey so badly? The Doctor commonly refers to Mickey as an idiot or pretends to forget his name and calls him Ricky.
In my opinion, Mickey does nothing to deserve this treatment. He is very kind to Rose, even though she never sticks up for him and leaves him behind over and over again. Mickey has also helped Rose and the Doctor many times. He always uses whatever he can, like his knowledge of computers and his vehicle, to help them out, but they never seem to appreciate him.
Some people might think that the Doctor is jealous of Mickey’s relationship with Rose. I find that really hard to believe because Rose clearly likes the Doctor better than Mickey, so the Doctor has no reason to be jealous. It makes me dislike the Doctor when he treats Mickey like this. The Doctor acts like it is one big joke, but it clearly hurts Mickey’s feelings. In the episode “School Reunion,” Mickey realizes that they treat him like K-9 when they make him wait by the car.
Based on the look on his face, I don’t think Mickey thinks it is funny. Why does the Doctor not value Mickey? Is the Doctor just a bully? I’m not sure what the answer is, but I do know that I am disappointed in the Doctor when he treats Mickey like this. I expect more from him.