SUBREDDIT: r/relationships
TITLE: Does it impact the ex for you to be polite and forgive?
POST: Just asking because me and my ex are supposed to talk soon after I've request NC for a 3 months. He's [22M] contacted me [22F] twice so far and I've just been polite and brief. 

I do want to him realize the weight of his actions and how he's been really shitty. Is the best way to approach it to be nice and forgiving, but tell him I can't be in his life because he's hurt me too much?

I know you might say focus on myself, because I might not be able to affect him at all. Or it would be best for me to move on, which I have been for the most part. I say that because I haven't been tempted to talk to him, and I definitely don't want him back. But I know I haven't made it all the way there yet. And I do forgive him; the only reason why I want to make an emotional impact on him is that he's somewhat selfish and hopefully this can help him realize some of his darkness. 

Not possible maybe, but please humor me. It's interesting enough to gain insight in emotional scenarios. It's kind of hard for me to put myself in his shoes.
TL;DR: 
When telling someone you don't want them to be in your life anymore, should you be utterly indifferent, angry, or forgiving to have the most possible impact on them?