This is my first Sweeney fic, so please bear with me. We're not in revival- world, however, Sweeney is very Michael Cerveris-esque in appearance and demeanor. Lovett's characterization and appearance would be closest to that of Patti LuPone in the 2001 concert.
This woman could be the death of him.
Sometimes he watched her when she had her back to him; watched her scrubbing dishes or rolling dough, and every once in a while he could fool himself into thinking she was Lucy. On occasion she even hummed under her breath like Lucy used to do. With her back to him he could fancy her tangled mess of auburn curls into Lucy's flowing blond locks; her hands, scratched and rough from work, into Lucy's delicate, soft ones; the shrill tune she hummed into a brighter melody that Lucy might have known. But just as he'd begun to believe it, she would turn around and jolt him from his reverie. She wasn't Lucy. She would never be Lucy.
In the daytime it was easy to hate her…or to dismiss her, at least. There were other things to be done, and he could busy himself upstairs without having to see hide nor hair of her if it was a busy day (and these days, it usually was). Nights were harder. They had taken to sitting together in his room, he reading or writing and she sewing or knitting or sometimes doing nothing at all. It wasn't that he minded her company, for he didn't, but he often felt he needed to guard himself around her…for his own sake and possibly hers. She might not be beautiful as Lucy but she knew how to tempt him—parading around in her frills-and-lace robe in the mornings, leaning close to him and breathing in his ear while he worked on the bodies down in the cellar. And he hated himself for giving in, for betraying his Lucy with the likes of…her.