Card 1 - person 1 Queen of Swords.
She has her back to the Devil, not wanting to admit her deepest awareness that the relationship is troublesome, that it ties her to things she does not want.
Its as though she can't quite let go to the idea of it, perhaps it seemed a good match on paper and so her theory was that it would all work out.
Card 3 - person 2 - 10 of swords
10 reflect end of cycles, about manifestation and completion. For this person then, the relationship has also run its course but not in a positive way. Its as though all the doubts and worries have become manifest in the relationship.
Looking at the swords and how the 2 last swords seem stuck in the other 8... He feels that both of them are tied together..
Swords relate to legal matters, so perhaps they are tied via marriage?
Both of them are swords, so they know they want to cut the ties that bind in the Le Diable, card 2, the interaction. They are stuck in a loveless relationship, stuck together due to legal issues, perhaps marriage or mortages etc, and so neither of them think its worth splitting. However, it seems full all that venomous communication, of that repressed energy that is like a volcano in Le Diable.
Perhaps even though the relationship is sour and ended, they both enjoy the carnal side of the relationship? Or perhaps the reason it is all gone so sour is that one of them betrayed the other with an affair.
I am thinking it was probably Partner 2 10 of swords - as that can be linked in with betrayal.
That may also explain why the Queen cant stand to look at the situation and see feels betrayed and would like to stab partner 2, but cant, as Queens are still emotional parts of the Honour cards and so still loves partner 2?
Just my thoughts.