Abaddon is the Biblical term for the place of destruction - Hell.
On a roundtable for comedy actresses put together by the magazine The Hollywood Reporter, Laura Dern commented her surprise regarding the journalist questions about the show. According to Dern, many of them emphasized the imperfect personality of her character, making the actress wonder if James Gandolfini or Larry David (stars of The Sopranos (1999) and Curb Your Enthusiasm (2000), also on HBO) were asked the same types of questions, considering their characters are praised for how flawed they are. Dern reveals that she just assumed the audience would be interested in seeing a female character whose strength and comicality came from her extreme behavior, and that she never got those questions when promoting independent movies, where she had played characters with similar traits.
Because Creator Mike White wrote all the episodes by himself, without a writers' room, every season was fully written before each shooting.
Originally, season two had ten episodes, but when HBO cut the order by two, Mike White had to re-write some things, like a storyline where Amy's sister stayed on the house for the whole season.