Should She Leave, Or Should She Stay?

Or should she come back, another day...lol don't mind me, just felt like singing that old school song 'Should I leave,Should I stay' (is that even the title?) anyway, can you advise this young lady

OK I have been seeing this guy for a while now in short we are dating its been up to a year close to a year we started dating and I love him yes I do but the issue here is that whenever we are going out maybe to buy something or to chill out around the town it happens that if we run into a friend (his friend) he will ask me to go to the back seat for the guy to seat in the front but for what? the first day he did that I respected him and did exactly what he said but he has been doing this every time we see any of his friends on our way going out and I don't like it,,,,,assuming we all left home at same time including the friend I can seat at the back I don't mind but asking me to come down in the middle of the road just for his friend to enter I don't think I can take it any more and mind u for those of u that will start asking me to go get my own car if I don't like what he is doing I have my own car it won't be nice going out with different cars on a date since we can easily use one either his or mine
another one is that he is a hard smoker he smokes anything smokeable just name it,he drinks too but not much tho I'm OK with that one the worst is that he stays out late almost every night, I have tried discussing that with him on several occasion he always promised to change but for where he is getting worst everyday I really don't know what else to say or do to change him because I think I have done everything possible to atleast to make him reduce it but its not working,am thinking of quitting still having a second thought about it that's y I opened up for u guys to help me out