I think your own approach makes sense to me. However, you caveat the issue by discussing how you behave differently with people you are willing to write off as friends.

So I would think that also applies to your friends' behavior. Another possibility is that they are either very passive when it comes to relationships, or that they know that they will likely get over whatever it is on their own so there's no need to rock the boat in the meantime (they're easy going). And if they're your friends chances are you already know if the latter is typical of their personalities.