Tully (2018)

While this has not yet appeared on an Oscar short list, I think it is likely to be nominated in at least the category of Best Actress given Charlize Theron's performance as an overwhelmed mother having her third child.  The other possibility is the screenplay category, which Diablo Cody wrote, and is just very well told.
This movie unearths uncomfortable truths in a wry, wise way. It features Cody’s hyper-verbal brand of snark, cynicism and subtle poignancy, but it’s tinged with the wistful perspective that comes from hard-earned maturity and experience.  The term bittersweet comes to mind.
The other truth it it mines is that when things are truly stressful, couples do not always communicate clearly with each other nor do they always support each other optimally.  This is a more or less healthy marriage where the ending comes just as much of a surprise to the husband as it does the audience.  Well done, but a bit painful (as a mother of four) to watch.