I can't imagine

You usually follow it with a how or what clause. For example, I can't imagine how tired you are. You can also use it as a standalone reaction. If a friend tells you a long, stressful story, just say, Wow, I can't imagine. It works for both very sad things and very amazing things. It is the ultimate 'I am on your side' phrase.

Use it when someone shares a big life event. Use it at work when a colleague is overwhelmed. It is perfect for texting a friend who had a bad breakup. Use it when someone achieves something massive, like running a marathon. It shows you recognize the effort they put in. It is great for building trust in any relationship.

Don't use it for tiny, everyday problems. If someone forgot their umbrella, I can't imagine sounds sarcastic. Avoid using it if you actually *have* experienced the exact same thing. In that case, say I know exactly how that feels. Don't use it if you want to sound cold or strictly professional. It is a 'heart' phrase, not a 'head' phrase. Also, don't say it if you are actually bored by the story!

English speakers, especially in the US and UK, value 'emotional intelligence.' We often feel awkward giving direct advice. Instead of telling someone what to do, we use empathy phrases. I can't imagine became very popular as a way to be supportive without being intrusive. It acknowledges that everyone's experience is unique. It is a very polite way to handle intense emotions.

You might hear I can only imagine for a slightly softer tone. Some people say I can't even imagine to add extra emphasis. In very casual settings, people just say I can't even. That last one is a bit more 'Gen Z' and often used for funny or annoying situations. Stick to the full phrase for real empathy.