hotwheels

Hi everyone, this could be long but I would be greatful for you thoughts.
OK, my B/F of 3 years has mild paranoid schitzophrenia. He was diagnosed in 1992 when he was 25yo.
Since the day I met him I have never seen him as being any different to anyone else I know. Yes he would get moody at times, bad tempered, doesn't like crowds as this is when he hears things. I don't like crowds either so most of the time we would try to avoid that type of situation.
I have noticed that he takes things more personally, if someone supposibly says something about him and he may even take it in the wrong context as to which it was said.
The problem lately is that he is making megga mountains out of things and he will go off his head about things. I find this embarrassing as he does not care who hears or where we are. I will give you an example: yesterday I was driving and he said to me go left and it will be quicker, it wasn't quicker he did not give clear instructions of where we were going and it was peak traffic. He could tell I was not happy and got mad shouting and carrying on in the car. My reaction was to keep my mouth shut and put up with the situation till he shuts up. I had a smile on my face and he accusses me of laughing at him. (I wasn't) but at the same time I say to him when he does that does he expect me to be submissive to him as there is no chance of that. To try and cut a long example short, when we got back to his place I was meant to go in for a coffee, I said that I would just rather go home (1 hour drive anyway). He yelled and carried on out front of his place and threatened me with things like, you laugh at me again and I will smash you in the mouth etc etc.
That night he rang me and apologised said that he was going to the docs today as he didn't think his tablets where working and that he knew what he did was wrong. He told a friend and his parents what he had done too.

The thing is...he is not a violent person, the opposite usually.
Is it likely that after 10 years on minimal meds, stelazin and melleril i think they are called.,one and a half at night. that he would change??
It is school holidays, there are people and screaming kids everywhere you go and I have 2, one of which is a 16 yo daughter who is not the nicest to him, could this be creating more stress and bringing on his behaviour?
I love him very much and know that he loves me but what am I suppose to do when he has these tempers? I usually say nothing at all and let him rant and this is when he accuses me of laughing at him and he just carries on even more, if I gave in to it all that would just be saying it is ok for you to act this way and treat me like this so I won't do that.
It worries me that this is going to continue and he will do this at a family gathering or in front of friends or anyone for that matter.
Sorry this is so long but if any readers have been in this situation from either side please post me your opinions. Thankyou.