Please advice no judgment :(

Pip • Pregnant with a little boy • c-section is booked for 4th July 2016 at 8am ✨
Me and my partner have had a very difficult relationship. He's either so lovely or so horrible. I've rang the police on him before but I took back what I said so he wouldn't get arrested as he apologised and said he'd change. 
So this weekend he'd let me down and I told him I was let down and disappointed (that's it, I wasn't horrible) and with that he kicked off. We was in the car he kept slamming the brakes and driving crazy to the point my legs are bruised. I kept shouting let me out and he wouldn't for ages. When I got out he wouldn't leave me alone.. He was calling me so many names saying that it's all my fault because I'm a cunt etc and treat him like shit (I promise you I don't, I am too madly in love to ever hurt him) he kept telling me he would drag me in the car or put me in the boot.. In the end I've had to give up and let him drive me or he said he'd go to my house and wake my family to "sort me out" when all I was doing was standing crying asking him to go. He's told me he would stop this kind of behaviour. He even made comments like "no wonder your mom beat you, look at you" and he kept spitting at me. Now he's just sat out my house in his car crying making me feel bad. I love him so much, I just want him to change. But I don't know if he ever will?