Good morning, dreamer.
The friend in your dream represents either himself (meaning, your view of him), or he represents any situation in which you do not behave as you are expected to. I get this from your description of your disparate musical tastes. Your peers seem to think that this is something which will make or break a relationship - and how shallow is that?
His family's displeasure over your association would seem to point out that he has pressures on him that are similar to yours - other people who don't think you should associate. The fact that you end up kissing is a rejection of these values - you are deciding your relationship.
The strange mixing of his house/your house is a dual statement. On the one hand, it says that you can make the situation work in spite of others trying to discourage you. On the other hand, the consequence could be that you will not feel comfortable with your life for a while. It's your house/but not your house - you're not totally in command of your own fate, at this point. Possibly a compromise will have to be made.