13 months for me, and I still can't look at ex, it's not a conscious thing it's just something that I realised happened recently. But he is not the person I thought he was and when I think about the way he has treated our DCs, it makes me very angry.
I know it's hard to do, but like others have said, don't respond to the baiting - because you will get it. Only respond via email or text and then only to the necessary emails and not the ones trying to draw you into a fight. I don't do chatty emails I just type down the facts, so drop off at 9.00, pick up at 5.00. That type of thing.
It's easier said than done I know, but I had all ex's emails sent to another directory and at first I used to check it every day, but now it's down to once a week. If he's sent one of his crazy emails I read it, might have a laugh about it with my friends, but I'm able to leave it now. I used to respond but in the end that didn't do me any favours. In fact it was making me ill, I had really bad insomnia. I had to draw the line.
Five weeks is no time, it will get better I promise, but it'll take a little while. Keep yourself busy with no time for brooding.
What makes me feel better is getting on with my life and being the person I am and not the sad person he made me. I am genuinely much happier today than I ever was in my 17 years of marriage.
Good luck with your future.