The 29-year-old singer alleges that Sammi is planning to reveal the gritty details of their turbulent romance - and he is unimpressed.
The on/off couple began dating in 2007 when Sammi posted a number of sexy photos on Lee's MySpace page, and they now have a three-year-old son called Rain.
But after hearing Sammi was about to tell all, Lee blasted: "No I've had enough of it!!!!! I'm only a person!!! I've had enough. Loved ones selling stories!!! Takes the piss!!!!
"Selling my story on my abusive relationship over the last 5 years!!! All the sh*t I've been through. Sick of it! Now you'll know the truth!"
He went on: "When someone threatens to go public with your relationship again! Let's go f***ing public!!!! Kept it to myself before!!!! Come on???
"You can't say sh*t Sammi! Telling me your gonna sell a story as a weapon hopefully this will shut you the f** up!!! Stop using who i am."
Bizarrely, Lee then insisted that he actually wasn't bothered.
"I honestly couldnt care less!! Do your worst!!! I've set it up!!! Tell me your gonna sell another story! Good! Hope all you f***ers enjoy it," he added.
"Ready!!! She's selling her story!!! Already told me!!! Done twice already!!! Enjoy it!!! Read all about it, read all about it!! F*** off!
Lee then went on to give the phone number of the journalist Sammi is apparently in talks with.
"Just in case you wanna sell a story on me ring this number! It's what Sammi rang before... 07********
"She will be most helpful!!! Also tell her f*** you from me. 07********* just incase you didn't get it.....x"
Lee ended his rant by claiming that he will be deleting Twitter because he social networking site 'does more harm than good'.
"F*** all u wankers on here!!! Some people have killed themselves over Twitter!!! This site should be banned!!!"
Couldn't care less, eh Lee?!
What do you think of Lee's reaction? Let us know in the comment box below.
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