@BannaBanna1
Serious question; what do you hope to gain by going back on your own? You already know he'll lie. Lie, lie, lie about how he'll 'change', how he's seen the 'error of his ways' etc. But you have seen and heard all that before, many times. Why do you think this time will be any different?
Read @OlderGlaswegianLivingInDevon 's post. You need to understand that you could be in extreme danger if you allow yourself to be alone with him. Violent men who have been 'thwarted' become even more violent.
I understand your guilt about DS7. But that guilt is misplaced. Your separation is better for the children because once you get over this 'hump' you will be providing them with a stable, calm, nonviolent, peaceful home. That is what they need to see, what they need to model. Not a home full of abuse and violence. Because as the old saying goes "Children learn what they live" and right now what your DS will learn is that violence against a woman is acceptable, because you willingly returned to it. In his mind, you will be admitting you were wrong to leave a violent man. Your DD will learn that she should expect to be hit or pushed because that's 'normal' in a relationship.
You are thinking 'in the moment' when you need to be thinking 'in the future'. Again, the time will come when this will be a blip on your life's radar. Stick it out, see if you can get counseling for your DS so he can truly explore his feelings in a safe environment and learn that sometimes we cannot be around people we love, but that the time will come when he will be able to see his dad, once you are all safe and resettled.
Please, please do NOT go see this man!