Yeah, I don't like this answer at all. I also frequently end up in awkward conversations due to my coupled-but-often-socialize-solo status, and I wish like hell they would stop, but the solution to other people pushing gendered mononormative norms is not for my partner to obligingly fall into line with them.

One deflection the LW might use is to recast it as her being at loose ends because her partner is busy: "Oh, husband is fine, but he always watches [TV show I hate] on Tuesdays. Sitting around the house while he does that is no fun, so I'm looking for a way to occupy just myself!"