Maybe I could not explain myself better, I am not saying she is prudish not even remotely. She fucks around, she lets people think she fucks around, she is a bad girl. So she is not lying to Holly or Lena about that.
What I tried to say she was expecting different from her life. You mentioned stalkfap, let's talk about that one. There was a scene where she said to Lena that doing Stalkfap is not her dream, she is doing that out of necessity but she is not ashamed of it, she embrace that part of her life and gives her best. Almost every conversation with Lena, she somehow mentions or indicates what she is doing is not what was she expecting from life but it is what it is, circumstances brought that life to her and she is making best out of it. For the off-screen sex if I am not mistaken, always people assuming not certain knowledge.
When she flirted with Mike, Jeremy and Lena assumed they had sex but we don't know. Everyone assumed she had sex with Billy but when Lena asked about it she brushed it off with did not have opportunity. Never gave in to Jeremy's advances, when she really considered it she vetted him. She did not follow the advice she gave to Holly, she is a woman and he is a man, he is after her why not give-in as she suggested to Holly. She holds grudge against Cherry even though she does not have any real beef with her and Cherry did nothing bad according to her playbook. She always suggest caution to Lena. She does not even care her party when her best friend needed her, a bad girl would resume to her birthday party and even get angry to her friend for downing the mood but she did not.
So what I try to say, she does not lie she is not a prude but she is not a slut either. She embrace what life brought to her and try to make it best out of it. And when it comes to find a partner; she is careful, she is cautious, she is hesitant. She can understand her power as a woman and acts according to that. I don't think comparing her to Jessica is not entirely correct. Jess did not know what she was expecting from life but I believe Ivy does.
If Ian becomes a chad, loyal, loving, caring, strong and successful and also not involved with Holly or Lena or Cherry she would become a loyal girlfriend and perfect wife in the endgame. That's why I think catching Ian with Cindy will probably have huge effect on her path also.