Eh, not going to respond to this whole rant because you've greatly misunderstood major parts of the story and let your preconceptions shade everything else.
Did Lucy do wrong in the story at times? Yep, and I'm not here to defend her but clarify some major story points people seem to forget..
1. She's half fairy, meaning she LOVES sex with anyone. She would have jumped on the MC from the start if the curse wasn't making her want to be with him above all (and not want anyone else with him), but also make her nauseated or have the idea of being with him repugnant.
Once the curse is lifted she has no problem bringing the MC in to her escapades and is finally able to express her actual feelings when she gets back to 'normal'.
2. You act like there never was a curse.. Remember that the curse was there to both want him, and not want anyone else to be with him, BUT make the idea of being with him a repulsive idea. So all of the people that bitch about "she knew what she was doing!" well being conscious of actions that seem normal at the time but you later realize were not doesn't mean what you felt at the time irrelevant.
It's like getting drunk, or mostly drunk, doing something or saying something to someone and only later when you sober up you realize that you fucked up. Lucy didn't KNOW she had a curse, she just thought she was having uneasy feelings about the MC.
3. No one knew there was an actual curse until part way into the story. Lucy did know she had done actions that real friends wouldn't, but it's like being bi-polar or having some other mental health issue that causes you to act completely different than your 'normal self' at times. You might not want to talk about when that flares up because it's very embarrassing and you might be making a bigger issue of it than what the others who saw it did.
All the rest of it, Rose, the futa spell, etc.. Yeah some of it was plot driven and the dev forced a good portion of it, but just saying that sometimes characters can't always control their actions and may not even realize they were messing up. The true character is when someone realizes they were wrong and apologize.
Please feel free to show me exactly where In the story is your account of the purposeof the curse.
I'm curious because I appear to have missed it.
The only mention of the purpose of the Curse in the whole story upto the choice of Lucy or no one.
Is that it makes her fearfull of even the Idea of her haveing sex with the MC.
There is no mention of any compulsion to do so.
As you stated she is half fairy so she would jump the Mc if not for the curse.
However nothing is said that indicates she is forced to want to do what she would happily do anyway if not for the curse.
Only the evil mage thing early on mentioned compulsion and that was to make her go back to him.
Thats the only time its brought up.
Nor any mention of it forcing her to stop him from having sex with anyone else.
That Idea apparently was entirely her own decision due to a feeling of jealousy over Rose.
Her reaction to that and what she then did points to what her real character is like.
And how she can and will behave if it suites her.
Again yes she felt Guilty and knew it was wrong but not enough to stop any of it.
But if she was compelled to act that way as you suggest .
Then guilt could be a risk to the plan behind the Curse so any Curse would be unliekly to allow that feeling.
I said upto the Lucy or No one choice because upto that point every thing she thought and did despite the curse.
After everything sofar once the curse is gone I would be willing to be Lucy's friend.
But why would I want to date her?.