My friend messages me on every platform. How do I politely say 'back off'?

In a world where we get flooded via Facebook, text messaging and more, a look at whether you can de-escalate a friendship without losing a friend

Q: A friend I know moderately but not terribly well sends me messages via every available medium - text message, messaging app, email and Facebook - far more often than I want to respond. How do I get her to back off without being rude?

A: I think what you're asking is how to de-escalate the friendship without losing the friend, and the answer is it may not be possible. It's a problem I think about relatively frequently, because it's tricky, and it feels disloyal, and love and friendship are two of the most important things in life and we reject them at our peril.