YOU ARE NOT RESPONSIBLE FOR HIS VIOLENCE
YOU ARE NOT RESPONSIBLE FOR HIS VIOLENCE
YOU ARE NOT RESPONSIBLE FOR HIS VIOLENCE
As others have said, these men feel that, when you "overstep the mark" they are ENTITLED to react. This sense of ENTITLEMENT is almost impossible to eradicate. Their thought processes go something like these:
"I love her and the kids but sometimes she drives me nuts...(so then I'm entitled to hit her)"
"I know I shouldn't beat her but she pushes me to my limit...every guy has a limit (so then I'm entitled to hit her)"
.....and so on.
Please beg, steal, borrow or buy the book "Why does he do that? - Inside the minds of Angry and Controlling Men" By Lundy Bancroft.
What you are going through is so, so hard.
Don't expect it to be easy, but please don't let him back into your house.
Allow your 5yo to believe daddy is away on holiday until s/he is old enough for you to explain what actually happened. This will not do your child any harm but to see you being beaten by your h will damage your dc's FOR EVER.
You have come so far since March... don't give up.