Yeah, it's confusing too (the fat neck). Is it meant to coincide with the likely reality of slow weight loss (Betty's storyline last season) which was explained by covering up her real life pregnancy?
It was interesting seeing Betty fat last season though now I'm wondering if Betty and Don's storylines are meant to be independent of each other for the rest of the series or are they going to cross paths again? Really hard to tell where they are going with her.
But I think she's getting even crazier, if that's even possible.