Whether you are off to the same college as your best friend, or you need someone to split the bills with, most of the time your best friend is not the person to live with. You might have known them your whole life, and you think you know them like the back of your hand, but living in the same habitat as them is bound to create some conflict. Living with roommates in general is tough to do, but adding the history of a lifelong friendship could potentially make things a whole lot worse. Some people can make it work, but for everyone else, it is simply not an option. For men it is less of a problem than it is for women, simply because of the way men are programmed, but overall moving in with your bestie just isn't the best idea.
You and your bestie have probably spent countless nights together, and even more days in each other's company, but nothing will prepare you for when you live in the same space. A lifelong friendship means that certain boundaries have been taken down, while others are a gray area. When you were younger of course you didn't mind sharing clothes, and everything you owned. But now that you're living together you have a new sense of ownership. No they can't wear your brand new shirt that you saved up for months for, why would they even ask? You start to get possessive, and now that you aren't as willing to share your stuff there could be tension when they take something without asking. That may have been how it was back when you were younger, but things are different in the real world.
And then there are the habits. You might be a total neat freak, and even though you knew your best friend was messy, you didn't realize they were a Tasmanian devil in human form. You like all of your stuff a certain way, dirty clothes in the hamper, dirty dishes in the sink or the dishwasher, and things like that. To your bestie, the floor is the hamper, and any flat surface is the sink. This is bound to cause some kind of tension between the two of you, and without the niceties that you would have with a total stranger, things can get ugly real quick.
Best friends that live together in harmony have a special talent that the rest of the population does not have. If you fall into that special category, congratulations, you are the 1%. If not, it's probably a good idea to stray away from the idea of living with your best friend. Living together creates tension and stress that can be detrimental to the overall health of a relationship. You can always find another roommate, but it is much harder to replace a lifelong best friend.