So, I'm back to that I really think Shelly doesn't think she's lying.
On one of the DR sessions in last week's episodes, Shelly admits to taking bits and pieces of info to both sides, recognizing that she's doing some lying. But, I don't think she thinks that she's lying or playing both sides or not maintaining the moral highground. But, on Sunday's episode she was pretty upset in her DR session about Rachel telling Jordan and Jeff that she would vote them out, etc. The lie was made more clear when the BB producers showed us Shelly's lie. And, yet she's still in the DR saying Rachel is lying and crying. Some people convince themselves that they aren't lying and would even pass a lie detector test. I think Shelly is one of those people, because really she can't be acting that upset ALL the time about Rachel.
I just think she has a different definition of lying and moral highground than I do.