Very sneaky and tit stirring from Jess. She left out the part where she made it very clear to him she's still interested but he rejected her and said he doesn't feel the same way about her now. She's clearly very bitter because ultimately she's been pied.
Right. I don't think she really lied or made things up. She was referring back to the situationship between her and Ronnie like two rounds of re-coupling before (which feels like ages ago in the villa) but she should have mentioned to Harriet that Ronnie has 100% shut the door to her NOW.