Please be careful, his brother is NOT PLAYING GAMES.....it is the culture & the VALUES that he holds to be truth.
Even if your BF doesn't hold those values at this point & hopefully won't fall to the pressures of family to return to them, you will always have his family's values that will always be different than yours to have to deal with.
I would strongly suggest that you get very familiar with the Iranian cultural/religious values so that you know what you are up against in this relationship.
You also need to remember that just because your BF has become westernized, he grew up surrounded with those values & really doesn't know all the western ways when it comes to family dynamics. It would be like you going to a foreign country after you grew up in your English family & trying to figure out HOW to do it in their style based only on your learned experiences. Doesn't mean that it can't be done & that it isn't done, but it's NOT EASY. Better to go into a relationship knowledgeable than ignoring all the facts.
These sites can give you some insight to where your BF's family is coming from & the values he grew up with:
Can scroll down to the headings Marriage, Family, Kinship; Socialization; & Etiquette (the rest is good information also)
http://www.everyculture.com/Ge-It/Iran.html
http://www.culturecrossing.net/basic...dent.php?id=98can select the topics at the bottom of the page