This?:
"If you didn't reject Olivia by the lake, you wouldn't have even gotten the option to "Deceive & Use Her" when she comes into your room in CH5. "CC2," which is the variable that triggers when you reject her in CH4, is required to even reach the menu that gives this option in CH5. Otherwise you're given only two options: which is to (A) Let Her Stay or (B) Send Her Away.
Again, it's possible to be on Liv's primary "dark path" without any of the forced stuff happening. The forced stuff is specifically for people on her alternate "dark path", which requires mostly resisting her advances and shooting her down... that is until CH5.
FYI, this also means choosing "Stop Her" either before you kiss her in Ch4, or before you finger her. Naturally if you are sexually active with Olivia prior to CH5, it means you didn't reject her and you're not on her alternate dark path"