A lot of people say that they don’t know what to make of him because one minute he’s nice to Sansa, the next minute he’s making her cry in the corridor. What’s his end game?
Thing is, he doesn’t have one. He’s an angry drunk. He wants to help Sansa and do right by her, but he also has a bad fuckin temper, and when he’s in a mood he’s horrible to be around. There’s no long term goal or reason for his actions; he acts how he feels at that particular moment. And that, I think, is the essence of the guy: he’s just a ball of impotent rage and frustration.
He’ll protect Sansa from the brunt of Joffery’s cruelty, but later on, when he’s off the clock so to speak and he’s had a few drinks, when Sansa is still trying to pretend like everything’s ok it pisses him off. He’s like “How can you keep lying to yourself, you idiot? Why do I even bother?” But the next day he sobers up and calms down, and starts it all over again. Nothing ever changes. His brother is still a revered knight with holdings and wealth, and everyone subscribes to the fiction that he’s not a complete monster. Meanwhile Sandor is still a body guard for a despicable little shit of a member of a family he’s been bound to since his birth. It’s the best he can hope for."
Sandor fans, and ASOIAF fans in general, read this. Beautiful analysis of The Hound.
(link to r/asoiaf, beware potential spoilers if you have not completed the series.)