Any one of those events isn't too bad in and of itself, except for the masturbating thing - maybe it's not technically incest or sexual abuse, although the way she describes it certainly makes it sound like the sister figured into the equation in some sexual fashion, but it's sure as hell pretty fucked up behavior, especially when she admits that she intentionally manipulated her sister into getting into bed/up close with her. I know if I were a pre-teen and I had a sibling 6 years older masturbating in bed right next to me, I'd be pretty fucking disturbed.
And personally, I grew up in a household of 5 kids, shared a room until I was 11 or so and often had multiple cousins, family friends etc. staying over and I never masturbated in the same room as any one else, or (as far as I know) had anyone else do it in the same room as me. I'm pretty weirded out that there are people here who think that's normal - worst case scenario, just go rub one out in the bathroom for fucks sake.
But yeah, other than the masturbating thing, any single one of those events can be written off as childhood fooling around, although even that makes me wonder what kind of home environment they were in. Yeah playing doctor or whatever is normal, but between siblings? and bikie sex slaves is a bit different from ''you show me yours I'll show you mine." But pile them all together, connect the dots with the way she describes her manipulative behavior (she even compares herself to a sexual predator, for fucks sake) and it's pretty obvious that there's something twisted going on. Maybe she was abused, maybe it's the environment she grew up in (those paintings... I won't call them "art"), who knows, but the chick is messed up.
And like others have said, if that's the stuff she felt comfortable putting in, you have to wonder if there's more she left out (although on the flip side, someone with the narcissism to write something like that at the age of 28 might be self-oblivious enough that they leave everything in). But at the end of the day, it's the hypocrisy that really shits me. Comparing all of that stuff she did to her sister to the way she describes the whole incident about getting fucked up on coke/booze/xanax, banging a dude then deciding she was raped because she was high is so absurd it makes me want to believe the whole thing is a sick joke.