As an active member of several narcissistic abuse support groups, I often see people post screen shots of their dialogues with their narcissistic abusers. They often argue with their narcissists or defend themselves, or they write heartfelt messages explaining how they feel and how the narcissist is hurting them.
DON’T DO THIS!!!
It may make sense in a normal relationship and it may seem reasonable when you are new to trying to deal with narcissists, but it is toxic to your well-being. If you argue with a narc or try to defend yourself, you will be backed into a corner. They will find a way to combat every word you say and blame you no matter what, so just don’t waste your time or energy. They aren’t worth it. You aren’t going to win or get through to them. When dealing with a narc, (if you bother dealing with them at all,) give short, factual answers. The end.
The worst thing you can do is pour out your heart to them. You may be capable of empathy and feeling, but they are not. Giving them a meaningful letter is like giving them bait to tear you apart. They will latch on to your secrets and insecurities and use them against you. They will use them to attack you and smear you. Don’t give them any more ammo!