incoming tl;dr. And wibbles.
[She would never be anything but truthful with Kira, and intends to do no less now. But she does hesitate a moment as she tries to get her feelings in order, because looking at Kira now, she finds her heart wavering.]
[How much stronger she feels just being in his arms is only the half of it. With Kira at her side, she feels whole in a way no one else can make her feel, no matter how deeply she loves them. A bond that can't be compared to anything else she's ever felt for anyone.]
[But, as ever, there is something between them that can't be ignored. Back home it was the war, then the grief from it, always something between them that was too big and important to push through. Ironic that here in this strange underwater prison they might have been able -- if she hadn't already succeeded in making that push with someone else. Someone who also needs her, and who she loves.]
[Lacus stays close, her fingers curled against his chest, as she speaks,]
I've been living with someone. His name is Neil. [And then a little smile, because Neil makes her truly happy. She wants Kira to know that, even though this news is hard for them both.]