Cyrielle ponders her current situation... she was one of Richard's romantic interests, yes, but of course, that was nothing definite, furthermore he clearly loved Camille far more than anything else... come to mention it, she also liked Camille quite well, though they were acquaintances at best, Cyrielle respected her maturity and professionalism as well as her detachment from the capricious madness of the setting...
Putting it into perspective that way, there really isn't much of a point in continuing to love Richard, presuming of course, that she loved him in the first place rather than merely being infatuated. After all, he was happy with Camille and Cyrielle was happy that both of them found happiness. This is generally where she would be expected to step aside, unable to reconcile her respect for the two with her love for Richard and, guilt wracked, close herself from social interactions for a while. However, she wasn't a stock character. She wasn't the sort of person who does that. Her view on love was rather pragmatic and realistic.
To put it plainly, Richard was far from ideal. In fact, everyone is far from ideal. Reality simply does not work that way, you don't have a soul mate, you don't suddenly fall so deeply in love that the person in question becomes your only option. If it did, then, Cyrielle had a feeling that rampant population growth and the associated resource depletion wouldn't be even a remote issue.
Richard was already in love and already in a relationship, she just had to accept that, and, admittedly, it wasn't that difficult to accept it. Firstly, it would be plainly obvious to even the most lovestruck fool, secondly, it would be easier that way, to accept it rather than to toil over it. Thirdly, there's always someone else, she didn't HAVE to be with Richard, especially true considering she wasn't even sure if she truly loved him. Fourthly and finally (because she preferred having such sets in powers of two, probably because she was accustomed to binary), it wasn't that much of an issue. She wasn't the sort of person who would care that much about it. Her brain dictated her actions far more than her heart. Just to convolute the metaphor, her heart was already nonfunctional and controlled by an eldritch entity nor does it perform any processing for that matter, irrespective of the aforementioned eldritch possession, so it doesn't have much of a say anyway.