Well, I thought it was strange that the daughter had not been primed by her mother to use an alias when posing as a journalist to interview Romer.
After all, she gave the game away as to her mother's identity - a silly omission.
I concluded that it was deliberate, that the mother was using the daughter to subtley threaten Romer. Romer committed suicide, or was he murdered, as the mother wanted her daughter to think?
The theme of the whole plot was 'trust nobody'. I think Sally's revenge on Romer was the intention all along - she wanted him dead. She had loved him and never forgave him for using her and betraying her during the war.
Though she got what she wanted she still didn't have peace of mind at the end. Either she was paranoid or was in real danger of being silenced.
Anyone think differently?