It seems that Garmadon still loves (or at least respects) his father.

When he says he wants to control Ninjago, he is also talking about his father. This means that he is not just interested in power over Ninjago, but in protecting and preserving his father's world. This shows that he has not lost his respect (and possibly love) for his father (for some reason), although he has lost all positive feelings towards the rest of his family. He perceived Wu and Lloyd as enemies, and he no longer communicates with Misako at all. However, for some reason, he does not...