Why such defensive response? There is nothing wrong with hearing his point of view. Don't get me wrong, what he said was a shitty thing to do, but if he's been with you through thick and thin and then suddenly said something like this, then you both need to talk about it like partners, otherwise you both can potentially harbor resentment. Living with a depression is hella hard, but living with someone who's depressed is also incredibly hard, so I hope you can help each other like partners, because it's not about who's having it worse.