I identify with Bubbles. As an excessively large and obviously strong person, I deal with a fair amount of people being scared of me, and that strains personal interaction, particularly with strangers who haven't learned yet that I can be trusted. And as someone who grew up in outer boondock, who expects the worst of small-town gossip and isn't all that socialized to deal with crowds, especially crowds of strangers, I do have a powerful instinct to be ALONE when I've got emotional stuff I need to sort out. People's constant insistence on "talking about it" is completely irrelevant as far as I can see; it's my insight I need, not theirs.
Finally, while I didn't get the worst of it myself, I'm like Faye in having gotten enough HorribleCrap(TM) in my life to understand some of the issues that face people who've gotten much worse. There's a point beyond which "normal" people are just not willing to consider dealing with, and once you're out past it, like Faye dealing with her Dad's suicide, you're dealing with the same USELESS responses from society at large that people who've dealt with stuff a whole lot worse are dealing with, and you know exactly how and why those responses are useless and you're in a unique position of being able to understand at least that kind of frustration.
I have a number of people in my life who have various degrees of PTSD from experiences that a benevolent God would have spared them. I have a lot of sympathy for that, and I've learned a bit about when they need a lot of space and when they need a little bit of boundary-pushing. It's always a balancing act, and sometimes it's hard to know how to be a good friend and emotionally hard to carry through on it once I've figured out what I need to do for them. But problems aside, they are among the best people and most powerful friendships I have ever known, and knowing them has been worth every second of it.
The kick is that Bubbles, who has serious PTSD issues, needs someone like Faye, who's dealing with / dealt with her own ration of HorribleCrap(TM) and knows exactly how useless are all the prior attempts at "helping" Bubbles undertaken by people who don't have that insight.
Anyway, this is my reading of it. I think Jeph is doing a hell of a job dealing with this.
I understand all the people saying they hate Bubbles and wouldn't want to be her friend; in fact that's a pretty normal response to anyone who's going through the kind of things that PTSD-affected vets go through. Not a helpful response, but realistically it's about what you learn to expect of people who haven't dealt with some kind of horror in their own lives.