To me it was always obvious that Ian's relationship with Alice was consensual in the sense that she knew he's an asshole and yet she kept choosing to submit to his whims because she simply couldn't resist being in that kind of relationship with a pretty fucker like him. It certainly didn't feel like Ian somehow blackmailed her or otherwise forced her to keep having sex with him.
Eww, I didn't need to know that.Alice isn't that old (more like 50ish), but you'd be surprised at the rising STD rates in nursing homes. Seniors do have sex drives.