I like your answer. Much better than mine. You obviously have a larger, higher functioning brain than I do. Especially this:

(odd what a strong moral sense he has, all things considered, isn't it)

That's one of the things I love so much about Mildmay is his strong moral compass. I think you're right to point out that creates a lot of the unhappiness in his life since he is compelled to actions that he knows are morally wrong.