Is he always like this or at times??

If he is always like this then forget it .. he is hopeless... no point in arguing with him...its more or less either take him the way he is or leave him.

If at times then try to find out the reason..it could be something at work, with friends or his past thats bothering him. May be his father was that type too... well there are several factors but you are only one who can decide how to deal with him...