picsinred is right. You have to ACT. You can't continue to be passive and nicey nice and hope he will leave like he said he would. You've a farts chance in hell of that happening. You gotta put your foot down and they wont like that, so you may have to call the police but you can't shy away from that, it's all or nothing. And if it's nothing, he'll be moving back in.
I say involve the sister. When she comes over advise her that his deadline for moving everything our is tonight and after that, if there's anything else he has forgotten, SHE will need to come pick it up.
The fact that you co-rent is potentially game changing. OP you have to start thinking 3 steps ahead. He will already be thinking about how he can use something like that to his advantage.
Does the money normally come out of your account? If so you can phone when he is gone to take him off the lease at least. He will also count on you not being able to afford the rent and try to use that to move back in.
Either way, best you move out as soon as you can too. If there is a while left on the lease, have you room to take in a lodger to help pay? That might also make it easier to keep ex away as he wont want to show his nasty side infront of a random if he comes over.
But yeh, start thinking threes steps ahead. And as if you are in a war and he is the opposing general and he wants to obliterate you. Because that is how he thinks about you for standing up to him and he isn't going to stop when you roll over and show him your belly.