unforgivable

An unforgivable thing is one that's so bad, people can't or won't forgive it. You might feel that someone's action was completely unacceptable and can never be made up for.

When we talk about something being unforgivable, we usually mean it's a serious mistake or hurtful behavior that went too far. For example, if you betray your best friend's trust, they might think what you did is unforgivable. If someone cheats on their partner or lies to their family members repeatedly, those actions can be seen as unforgivable too. In these cases, forgiveness isn't an easy thing for the hurt people to do, and it often takes a long time to heal. Sometimes, the people who were hurt might decide they just can't forgive and move on, especially if the person responsible shows no remorse or tries to justify their actions.