You need to learn the secret of their success how they manage to function as if nothing untoward is taking place in their lives, Pissy.
Compartmentalise.
You've sent your missive and instead of anticipating what his reply may be, stick all thoughts to do with him/it in a box marked 'do not open until necessary'. And it won't be necessary to open it until he responds.
When/if he responds, deal with it. And then back into the box it goes while you get on with more important matters such as earning a crust or scoffing krispy kremes while watching daytime tv.
Detach, detach, detach. It is what it is, what's done is done; it can't be undone, and you don't need to drive yourself crazy fretting about the how's, why's, and wherefore's, because it comes down to one simple fact: the guy's a deceitful, duplicitous, lying twunt and you'll be infinitely better off without him.
If he doesn't respond or fails to raise the subject when he gets home from work, don't mention it. Get ready, go to the party as if nothing's happened, and keep him in suspense.
No more emails/texts/phone conversations about this subject. Choose your moment to confront him in person and choose your words carefully - we wouldn't want him to be under any illusion that he can worm his way out of this one 
I'm a tad concerned about your title for this thread... you say you 'stood up for myself in his reply'. Does this mean you tend not to stand up to things he says to you? Has he put away physical violence in favour of verbal, emotional, and other forms of abuse?