I think Demelza is looking for the level of feeling from Ross that Demelza thinks Ross has for Elizabeth -- even though from my perspective, Ross left Elizabeth standing at the Trenwith window twice: first with Francis & then with George with the ultimate +1. I believe, but Demelza doesn't, that Ross & Elizabeth are "never, ever getting back together." I believe this not because of Ross & his real & imagined monologues, but because of what I saw from Elizabeth in that church.
In Ross' imagined monologue to Demelza, Ross states he wronged Elizabeth (any admission of wrongdoing on Ross' part surprises me frankly), that 15 years ago Ross would have given the world for Elizabeth (first love can be that way, but I don't think Ross & Elizabeth were ever built or compatible for more than first love) & that he still found Elizabeth so very lovely (the kisses all over Elizabeth's face already said that to me). "You changed me" Demelza actually heard much the same song and dance before. Remember Ross' "imperfect love" Demelza vs. "idealized love" Elizabeth monologue? I'm actually glad Ross kept these thoughts to himself this time. Who is he trying to convince -- Demelza or himself?
Perspective & knowing what you want is what you have is a gift. Fool me once, shame on you. Fool me twice, shame on me. Ross wasn't married with children when Elizabeth married Francis, but Ross didn't put up a fight then either. Elizabeth wants money & position, he sputtered at the time. In their conversation at the church, Ross reminded Elizabeth how George always looked at her -- & made a point of saying that he always knew it. Interesting. Unfathomable as it was to Ross (or George or Elizabeth herself for that matter) that Elizabeth would ever be with George & the depths to which Ross sunk to prevent it, here they all are. And, there was Ross coaching Elizabeth on how to maintain her fiction about Valentine and thereby maintain her marriage to George.
But after Ross kissed Elizabeth all over her face, it was Elizabeth who actually said the word "goodbye" & walked away with her head held high. Ross just stood there looking verklempt. Maybe because Ross realized Elizabeth doesn't just have to be with George, she actually wants to be at this point? Toads! Other than finally having it out with Ross as she ought to long ago, I don't think Elizabeth was out of touch with the times and looking for a reunion in that church. I also think Ross' blase attitude about "George's son" Valentine was the final wake-up call Elizabeth needed to lob the Holy Water on the ghost of her love for Ross. Geoffrey Charles is blossoming at Harrow on George's dime (whatever George's intentions were sending him there) & Elizabeth was quite the lady of the manor eating strawberries in bed with her man -- a man who is not unpleasant to look at IMO, thinks she is the most beautiful woman in every room & would never let her go. George is a mess, but Elizabeth has seen way worse, her cousin is married to it, thanks to her & her husband. Channel your power for good, Elizabeth.