Her neck is fucking filthy. I know, I know, diabeetus negrocathasis or whatever. I get it. But that is straight FILTH on her neck and no one will convince me otherwise. She hasn't bathed in weeks.
Cessation of hygeine practices is a common symptom of depression. I think it happens to a lot of depressed people but they won't admit it, even if they're open to discussing other aspects of their illness. Thing is, when you're so depressed that you stop washing yourself, you're also firmly in get-no-joy-from-activities territory. Amberlynn continued to do her favorite things up until very recently--eating out and shopping. And she only stopped because of shame/being too fat to walk; that's different from depression keeping people from doing things. So it doesn't seem to be depression that kept her from bathing, she's just a filthy disgusting pig.
I can't imagine being that dirty and going out in public and genuinely enjoying yourself, yet somehow she does. Doesn't she worry about how she smells? It's baffling.