For instance, lying flat on the floor, then scooting into the bathroom and supposedly fixing her nails, smiling as she's leaving the back of the house, falling down the stairs (on one shoe, understandable), being helped into Kim's car, blotto in the car at Kroger's BUT holding tight to the gear shift, on the way to jail in the police car suddenly screaming that she's been raped, first by 20 white men, then 3, id'ing 4, etc. etc.
I think her party behavior is just the latest episode in a long-standing pattern of mental instability and substance abuse.
I just had a thought reading your post. I remembered something the ex-hubby said about her wanting to dance and he didn't fault her for feeding her children. Wonder if she is not the one who wanted her to dance but him and the night this all happened, she was wanting to back out/not dance. She goes to him (or is with him) to tell him she doesn't want to - again - he beats her and has sex with her to make her submissive. This could account for some of her weird behaviour.