Ok, the first thing I think needs to be explained to your friend is that friendship is a completely subjective thing, and in fact as a general rule your friendship with your cousins will almost certainly deteriorate rapidly as you go through your teens. Simply because, contrary to popular belief blood is not thicker than water. He played with his cousin when he was younger, and they had fantastic fun because their interests back then were so simple; cartoons, lego, chocolate, mud and running about (because every boy under 10 years of age has pretty much the same interests.)cheesyman987 said:My friend is a very nostalgic and very passive person. He was best friends with his cousin when they were younger, and he's been trying to keep his cousin as a friend, and trust me when I say he will do anything to maintain a friendship. We hadn't spoken in about 2-3 years and he suddenly calls to ask if he can go to martial arts class with me. He is very dedicated to friendship (if only he was that dedicated to study, he might be doing better), and he wants things to be like they were in the good old days.
Now that their personalities are developing to become a more independent person it is stupid to think that they will still remain friends just because they are related. They need common interests, a similar sense of humour, to be interested in what the other has been doing, just the same as any other friendship, and from your posts it is clear that that is simply not happening.
If your friend cannot be friends with his cousin unless he spends all his money and time doing something he does not like to do, and if your friends' cousin does not want to compromise and do anything else, then, even if he buys COD and indulges in his cousins wants, the friendship is a complete waste of time and will have absolutely no redeeming factors. Your friend won't enjoy himself, his cousin won't really be enjoying your friends company and will treat him like crap anyway and come to resent him.
The best thing for your friend to do is to leave your cousin alone. It doesn't sound ideal but there is no magic option that will rekindle a childhood friendship because that friendship was solely based off them both being dumped together during family things and having to entertain themselves together, which worked because they had such limited, universal interests.
It allows your friend to buy the game he wants and spend time with people who appreciate him, and it allows his cousin to make friends who also enjoy playing COD, and to play his game until he gets it out of his system. You can't be friends with everyone in the world, nor should you.