Kelly Osbourne has launched a foul-mouthed rant against her ex-fiance Luke Worrall on Twitter.com, branding the model "the worst thing that ever happened to me."

The pop singer-turned-reality TV star dumped Worrall in July amid allegations of his infidelity, and she admitted the heartbreak hit her hard.

However, Osbourne has now lashed out at her ex on the microblogging site after a Christmas encounter with Worrall - and accused her former partner of using her.

In a series of posts, she writes, "Luke worrall is the biggest piece of s**t he has been trying to get back w/ (with) me... I only came home for Xmas to see him meanwhile he has been f**king 100's of girls... behind my back all he did was use me all girls beware of luke worral (sic) he is a using c**t! "

"He used me for my money and a free ride he is lucky I am not spilling the hole (sic) truth about what he did! He is the worst thing that ever happened to me I don't give a f**k what happens to him anymore."

"I am and always will be 2 good 4 luke worrall darling ur pretty face will only get you so far because u don't have the brains to back it up."

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