spam from own email address

Hello, I am getting emails like the one below, in which the header from is my own address. The emails contain text in a jpg image and claims my account has been hacked and demands $1000 paid to a bitcoin account. I would like to find a way to reject emails from my own addresses except from my

Re: spam from own email address

Thanks for all the suggestions: - I have an SPF record, but postfix not rejecting these, presumably because the enveloper sender is valid - I am not using SpamAssassin, but I'm coming round to the idea! - John: this idea seems simple and effective, I will give it a try. Many thanks, Ian Le