The grey heart emoji represents emotional ambiguity or indifference.
Unicode: U+1FA76
The grey heart emoji symbolizes a lack of strong feelings or emotions, often conveying a sense of neutrality, apathy, or indifference. It can also be used to express a sense of emotional distance or detachment.
I'm feeling a bit ๐ฉถ about the party tonight. Not really excited, but not opposed to going either.
The movie left me with a ๐ฉถ feeling. It wasn't great, but it wasn't terrible either.