Teehee, looks like I've grown some immunity to TVTropes: I only rapidly checked out type B (well, I checked the various types for comparison) on the page then closed it right away. I'm proud.
I don't quite agree, though. I'm in the impression that Marten is quite able to force himself into a relatively serene state, with the prospect of making it genuine in the long run, through some kind of autosuggestion. We've seen him doing it before, like when he reacted to Faye having told right away to Angus the story about her father's suicide. He was upset at first, but overcame it for the sake of Faye. I don't think he simply had changed feelings based on Faye's explanations, said explanations rather gave him leverage to set aside his initial emotions as irrational, and view the situation more positively. So, it's a bit of a facade, but there's more to it.
Have none of you ever forced a smile on your face, only to find out it actually made you feel better? Granted, it doesn't work everytime (and neither does Marten always pull it out successfully), but it can work for realz.