First, you have to decide what you want! Do you want this marriage? Do you love this man? if yes is the answer to these questions, then do what you believe...that your m can be saved.
he gave you a list of some things he is looking for: stop arguing, controlling behavior that he wants changed. Don't defend yourself, be friendly, do nice things for him but don't bend over backwards...treat him like one of your good friends.
I know you are sad...there were MANY times my h screamed in my face that this was it, he was done, it was over, he was seeing someone else...but I stayed strong, calm, kept BELIEVING my m was going to be saved. Even when I went to d court, I BELIEVED!!!! You are right don't focus on what he's saying...the only thing you can know for sure in this type situation is HOW you feel! Get that right, then you can stand firm no matter what he throws at you. Even if this time he says it is for real you are going to believe in YOU, that you are worth this m, that you can change, that you are changing, that as long as you are changing you have every chance in the world for this to turn around.
Now dust yourself off, lift your chin up and believe! Don't let his little insecurities get to you. YOu are awesome, trying so hard, looking good....he's a fool who is being utterly selfish!