There are very few cases in which a prompt response is required.
The more infuriating, unnerving, frustrating of messages demand that you take a step back. Clear your mind, go for a walk, take a full night of sleep, pause for a few days if necessary. Process what is going on within you, try to not second guess the sender, talk about it with someone you trust. Honestly evaluate if an answer is really needed. And if it is, when the time comes, craft it as if the person you most love and respect would be the recipient.
The damages made by prompt responses are immense. What is written or said once can never be taken back.