bitcoin is a p2p currency. the only way it can die is if people stop using it
I cannot agree with you, bitcoin is not only a p2p currency, it is something more than that.
You have many places where you basically deposit the bitcoins on the exchange, and you put up a sell order.
It does not have to be neccesarily one investor buying you bitcoins, but they might be distributed among bigger number of traders.
Obviously, you can use only p2p transaction services, such as localbitcoins.com to just obtain bitcoins through trade which includes cash, or bank transfer.
When you send a transaction to one peer even when your coins is at an exchange, isn't it peer to peer transaction?
It is when the developer stop developing Bitcoin and miners stop mining it, even with people who are willing to transact but no one is mining, network will not move since no one will mine and solve a block. The network being stagnant means a sign of Bitcoin being dead.