Wow, what a nightmare. I hope you're treating yourself kindly; you really need to cut yourself some slack.
I see you taking a lot of blame in the way you've worded things, and not letting the other people involved own their own faults, mistakes, and mis-steps. Let go of the blame, you really do need some slack here.
Without knowing the other sides of the story, one can only make inferences from what you've said here, so take this with a grain of salt. But WTF is up with FWB?! Do you think some of your seemingly low self-worth could be stemming from how he didn't stand by you after he'd married and committed to you, and had his commitment to you annulled when you were being treated for PTSD? What gives him the right to use you exclusively for sex, tell you not to be affectionate in a public meeting because he has the hots for someone else, and then create scads and scads of drama for you because he wants you all to himself for sex but not have any duty to you emotionally? I am ALL about having friends with benefits, but NO ONE may treat me like that. NO ONE should treat you like that, either.
From what you've typed, I see an awful lot of fault on FWB's part, and little to none on yours. I don't think you've done wrong. It really seems like FWB caused this drama and frankly, were I you, I would consider cutting him out of my life. I do not want or need that kind of drama from someone who only uses me for sex. If his only benefit to you is the sex, then it might be time to invest in a good vibrator. The sex might not be as good, but vibrators rarely cause drama for prospective relationships.
As for E, I think your views are justified. He does sound like a skeezer, not following through, etc.
So, do cut yourself some slack; you've been through some rough stuff and deserve to be kind to yourself.