Xenoliya wants to marry Thandren because he's rich, titled, handsome and single.  If she finds out about his love for Suravi, she'll be very...put out.  If she finds out that he hired an assassin to off his uncle, she will be willing to blackmail him into marriage.  She will magnanimously allow him to keep Suravi as a mistress, provided no one finds out about her, but he has to marry her and treat her as his wife (including sleeping with her, obviously), in order to shut her up.

If Thandren or Suravi can find it out, she has a secret as well: she has risen to where she is in the Warlock community through blackmail and murder - mostly the latter.  She's careful enough that not only do they look like accidents/natural causes, but they're never traced back to her.  Those she has killed were obstacles to her rise and/or people she considered weak, unable to best serve their fellow warlocks and the throne.
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The Temple requires a Trial of its priests-in-training: this Trial requires the priest/ess to journey into a labyrinth that lays beneath the Temple and, indeed, below most of Silvermoon.  They enter with no weapon except their spells (no mace, no wand) and wearing *only* pure white holy robes.  There the magic of the labyrinth makes them confront their deepest fears, forgive themselves for the acts they feel guilty over, work through the conflicts in their souls, and ultimately, encourages them to give up that which holds them to the material plane.  The trainee will die and be resurrected (literally) in the course of the Trial, and is supposed to come out purer and wiser for it.  It takes days, during which, of course, the trainee cannot leave the labyrinth (the only way out is to go through it).

Suravi is doing well until asked to give up that which holds her to the secular world.  This particular test is given when the trainee is attacked and dies.  If s/he gives up their ties to the secular world, they will seem to ascend as if going to another, higher plane, the spirit plane; they will then be resurrected.  Suravi is held to the mortal plane by her feelings for Thandren, and she refuses to give them up...thus she remains dead.  There are Watchers who oversee the Trials, keeping what goes on there in strictest confidence; when they realize she's not being resurrected, they intervene and pull her from the labyrinth.

Of course, now her training has been set back.  Hearing why she didn't release to the spirit plane, the higher level priests become worried.  Love is a wonderful thing, but...without that final release, she cannot be a fully fledged priestess of Silvermoon.  They tell her this and let the decision be hers.  She declares she will not give up loving Thandren and sadly goes to her room in the Temple to start packing.  

A knock comes on the door and a sealed message is all that's there when she opens it.  She picks it up and is informed that she can continue to receive training, in secret, from certain priests scattered around Kalimdor and the Eastern Kingdoms, if she can seek them out.  These are priests who made the same decision she did, and yet have come to understand the light as well, if not better, than those who succeeded in the Temple's trials.  The Temple has a reputation to maintain; these priests do not.  Included is another piece of parchment - an general introduction letter to these hidden rogue priests for her.
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One of Selrone's backers is a young man named Paeron, and while he pretends to support Athame's reclamation of her status, he secretly wants to undermine her; she's stronger than Selrone is, and with Selrone in charge, Paeron would be the real power, as he is Selrone's most trusted friend and confidant in the family.

Other people at the party: Reilya, Paeron's sister, but genuinely on Athame's side
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