Once a person is completely mentally and emotionally checked out, they'll start to say things that slowly clue others in to just how spent they are on all levels. AdvertisementOnce someone checks out mentally and emotionally, they'll frequently use these phrases in casual conversations1. This word can be heard as dismissive, but it's frequently more of a sign that someone has mentally stepped away from the conversation. People who have completely checked out may describe themselves as tired because saying they are mentally and emotionally exhausted feels like too much to explain. When someone is no longer present mentally or emotionally, being alone can start feeling easier than participating in relationships.