Jekle and Hyde how to go about this?

[Southernscape2017]

I've been with my partner for four years and 8months ago we had a baby girl.
The first year or so we had a great time going out and fun holidays. He's from Italy and we regularly visited his family over there and I quickly learned Italian.
He really wanted to children and although from previous relationships it had been pushed away from my mind, I loved the idea.
Before you know it we're engaged and getting married. However I got pregnant due around the wedding date so we postponed the wedding.
The last approx 2 yrs he suffered with sleep apnea but manged to get it under control around the time of the birth of our baby. During this time he began to get extra moody and small things were big to him and always seems to feel wronged by his boss, the government, whoever really. He will still now literally gets angry over spilt milk.
His sleep stuff is sorted but he is still a Jekel and Hyde. One day he will be angry at the slightest thing and tell me what I'm doing wrong and when we don't agree be v angry.. Next day he'll be helping with the housework and talking about holiday like there's nothing wrong.
He has slowly whittled away at me so he controls most aspects of my life whilst making it seem like he hasn't.
We're about to start counselling but I just feel like it's over. He's been vile to me and until about a month ago had little support from him with our baby or just being nice . Even now there's smiles I just feel we're pretending I just don't know how to go about it or f maybe he'll refuse to leave the house which we have both mortgage. Maybe he'll get nasty?
The emotional abuse he's given me is hard to prove and sometimes makes me feel like I'm going crazy. Where do I go from here?

The truth is you'll probably end up leaving at some point, why waste any more time? I'd leave before his behaviour affects your child.

I know I'm making it sound easy to leave and I'm sure it won't be but it never will get easier. He's whittling away at you and until you have no confidence and won't be able to leave.

Can you speak to women's aid?

What else is happening in his life? Someone going from being really great to someone short tempered is usually a sign of stress or something going wrong in his wider life he can’t control and is unable to deal with himself. I know the conventional wisdom on these forums is ‘leave him immediately!’ and perhaps that’s right, but before you do take some effort to understand the reasoning behind the change. He’s unlikely to tell you if you just ask, so it’s worth investing some time in some detective work. There’s something in his life that’s out of balance. What is it?

Yes perhaps speaking to women's aid would be a good call.
I have taken over a year on trying to understand what is bothering him, helped him get his sleep issues sorted, stressed how important it is to get possible depression looked at but he has not taken my advice. I have patiently tried to talk to him despite me being the one in more need of support when my baby was days and weeks old.
It was mostly greeted with anger despite me trying to help him.
He is perhaps frustrated that we are not living in Italy but I never agreed to move there, merely a yeah maybe one day would be fun, and this discussion was a few years ago. I met him here and with the issues we have had, I am reluctant to even think about moving there even further from my support network.