I don't know about you, but whenever a friend annoys or affends me, the first thought that comes in my head is, "I wish we weren't that close."
It's a shame, really. Ironic too.
I find that when you are too close to someone, somebody tends to start getting complacent; to start taking the other for granted.
This is when the jokes that are considered not cool come about, but nobody was the wiser.
This is when expectations get raised.
This is when a big, permanent fallout can happen because neither party expected to be betrayed.
This never happens with someone you're not close to (unless they're criminals out to get you.)
It's more comfortable.
There are no expectations.
There are not dirty secrets.
As ironic as it sounds, sometimes I do wish I wasn't close to some particular friends.
I guess the best answer is always keep a healthy distance no matter what.