That depends.
In my case, when my AXGF "left the building" for the last time, I was beyond done. Once the sting of her betrayal wore off, I got back on my feet relatively quick.
That said, my case isn't the norm. If you still have strong feelings for someone, those typically don't fade away even when they've hurt you. But what will happen, in time, is you'll look at him through a different set of eyes. Your brain will be able to process both the good and the bad about him. And what's bad -- the drugs and all the drama/chaos/carnage/insanity that comes with it -- will have enough weight and meaning to prevent you from allowing him back in the picture.
Doesn't mean you don't care about him. What it does mean is you've been there, done that, and you're not going to do it again.
Be patient. Keep doing the things you're doing. And, yes, eat something tasty...
