My first post was out of shock, but I realise it was snippy. To me the obvious reaction would have been to get the police to remove the H and then ask them to signpost me to further support to keep him away and I've been in an abusive relationship, more than once sadly. I know how muddled your thoughts can be and how exhausting it all is, mentally and physically.
I've also been the child of an abusive man. Staying or leaving should not be the choice of the child. I chose to stay, when I was about 15 and my mum asked me if I really wanted to pack up my little sisters in the dead of night and walk out into the cold. I said no. I've never forgiven myself for that decision.
I also think OP's plan is bullshit, sorry for being harsh OP, but I had a plan and then another plan and then another one...
Your plan is a way to protect yourself from having to make tough choices. You don't need a plan to leave, you just need to leave, there will always be a reason to stay for now, there will never be a right time to leave, if there was ever going to be time to end this it would have been last night. Just go.
I was aghast when people kept telling me that too, how can you just leave your home with nowhere to go and no money? You can, it is possible if you ask for help from the right places and it won't be nearly as hard or traumatic as you think it will.
If you really, honestly cannot cope with that thought just yet, and not being able to is not a sign of weakness or of not being a good enough parent, then at least get counselling for you and your child. You both deserve better than this.