(genuine interpersonal skills do NOT appear to be a strong point of Marth's unless the situation is "please join my army"!)
Probably because Marth has a lot of problems expressing his true feelings to begin with. Poor kid's just really messed up :/

Even if some of what I've seen in FE12 made me think she deserves better. :/
Part of me hopes that Caeda's able to help Marth heal a bit and overcome some of the obstacles.

...dammit now I want to write meta about this.