
The thing is, Ripley is neglecting her own health. Her pale complexion was noted by Wright and Etoire, and she had two nosebleed. The duke was extreme, but he did it because Ripley is pretty much stubborn and she doesn't know when to stop. She wants to do the volunteering mostly because she still works on her love project of getting Etoile and Wright together ( ̄∇ ̄")
The duke did manipulate her yeah(even threatened to cut Sylvia neck if Ripley so much as goes outside... Of course, this is a bluff but Sylvia pretty much believed in the threat lol. Iirc Ripley doesn't believe in the threat as well, but didn't argue because she has more work to do anyways). He also wants her to focus on marriage-- and to follow the schedule that has been set. And in the novel he said that she can focus on her work after the wedding.
That free lady statement, in the novel, it's actually more meant as he's not going to let her be free from him.
I cant be the only one who thinks what the duke is doing is super manipulative. Like shes literally doing voulenteer work and he bans her from going out???? Thats such a shitty thing to do. The fact that he also said i dont intend to let you be a free woman just raises ALL the red flags