Demi Lovato Sends 'Ex-Boyfriend' Wilmer Valderrama Gushing Birthday Message

Demi Lovato has fuelled more speculation on her alleged relationship with That 70s Show actor Wilmer Valderrama, calling him an "incredible man" in a birthday message on Twitter.

The couple have never confirmed their romance, nor have they commented on reports that they split last month.

But returning to the micro-blogging social network after a self-imposed break, Lovato wrote: "To the one and only @WillyVille - I only hope the world can see what an incredible man you are.. Happy Birthday Wilmer, you deserve it. :)"

He replied: "thank you my angel... #StayStrong"

Demi recently had to deny rumours that she had returned to rehab for an alleged cocaine addiction.

The former Sonny With A Chance star is releasing new music in the UK this month, with her US Top 10 hit 'Skyscraper' due for release on February 27, and her third studio album Unbroken slated for March 5.

Demi Lovato shines on the red carpet

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