Let me decode her, may be I'm wrong, but I strongly feel this.
She genuinly likes shilpa .. yes I saw this as shilpa fan n what she is being off late ...
reason:- 1. during BB day care, she insulted shilpa doll openly .. got bashed, she treated the doll so badly, but in same day ED, we see BB calling on to her to return the shirt which had shilpa pic, everyone else had returned and she didn't .. she wanted to keep it.
2. Also during torture task, she hesitates to trouble shilpa
3. During swingpool thing, she hesitates to accept that shilpa has no true frnd in house.
4. After Bandigi eviction, Acash reveals his plan to trap shilpa .. she seeks help from vikas n hiten to protect shilpa indirectly from acash.
then y does she behave so mean to shilpa on her face ?
She initialy started the act of flip to put sense into acash .. in that fake bitching phase, In ED, we see vikas giving opinion that along with positive personality all negative ppl will also go till finale, .. it was his opinion on the game, which is quite true as well, so she picked this very seriously .. she wants to compete with hina for negative slot n sail till finale.
Also madam has Jealousy problem .. she does not like both vikas n shilpa prioritizing others over her. Vikas manages her, shilpa snaps at her ..
Dil se she like shilpa, but for game, feels she can't be along with her n get lost .. so went against her .