I'm new to the forum, so I really do hope I'm not stepping on any toes by replying here.
Personally, if I were to see these cards in a love outcome, I would interpret them as telling the querent that she knows this is/was a toxic relationship (Devil), and she now has a choice to either move forward or be trapped by it (WoF).
As to whether the pairing indicates he will return, again I would interpret the cards as telling her that the choice is up to her, with a caveat that the relationship will be unhealthy if he does.