For those of y'all whose nightie style errs on the side of sweet, consider this Oscar de la Renta chemise at $69. It is quite lovely and the bow detail adds a sweet dimension. If you are not looking to pay silk prices, this is a very pretty option despite being made of polyester.
Here is a beautiful option with a higher percentage of natural fibers. This Stella McCartney nightgown is a silk blend which means it will have a bit of stretch but still feel very silky. The price is $300.
If you prefer bralette and matching knickers, this set from BHLD is beautiful. The bralette is $79 and the bottoms are $64. Both are made of a silk blend. The colors are more suited to bridal rather than Valentines, but I've heard of people needing breaks from pretty pinks. I don't claim to understand it, but I am here for you with shopping suggestions anyway.
And now for a cotton option. This beautiful cotton robe is from Plum Pretty Sugar and I desperately want it. It is $70 and has a matching nightgown. The ankle length nightgown is $52 and the knee length is $44. Pretty Plum Sugar has a ton of lovely patterns that you could mix and match, as well.
And if you are looking for something a bit more risqué and have $564 to spend on a piece of lingerie, click through the link to see a La Perla chemise. As I said at the beginning of the article, we like to keep Posh Purpose on the tasteful side of things so I won't post the image here.