That 'addict novel' search usually brings up Anna Zaires' 'Twist Me' series or maybe something like JT Geissinger's 'Beautifully Cruel'? Thing is, 'addict' is often part of the title, not a genre name. If you mean 'Twist Me', the core is a Stockholm syndrome story gone extreme. Nora gets kidnapped by a wealthy, obsessed man named Julian and taken to a private island. The plot is essentially the psychological unraveling and rebuilding of her identity under total control, but Zaires writes it so you feel the pull, the messed-up dependency. The key theme isn't really romance in a traditional sense; it's about the erosion of free will and how trauma bonds can feel like love. The power imbalance is the entire point, not a flaw. It's a book that makes you question your own reactions because part of you starts rooting for the captor, which is deeply uncomfortable.
Some readers dismiss it as pure dark fantasy, but I think it probes at something real about how extreme isolation and targeted 'care' from an abuser can rewrite a person's instincts. The secondary theme is the isolation of the setting itself—the island is a character, reinforcing the 'only us in the world' mentality. It's not a book I'd recommend lightly, and it definitely requires major suspension of disbelief regarding logistics, but as a character study in psychological captivity, it sticks with you.