Wilmer and Demi Back Together?

If the rumors are true, Wilmer Valderrama and Demi Lovato are back together again. While they've both been pretty secretive about it, he apparently couldn't let the occasion of her 21st birthday pass without some sort of public acknowledgment.

On Tuesday, Aug. 20, Valderrama tweeted:

I've been so proud of the strength & commitment you've gained 4 life, keep inspiring us all! Happy birthday my @ddlovato! With & by u always

The replies from other Twitter users were quick to point out that he'd called her “my Demi” when posting. (Apparently they even have their own celebrity couple mashup name: Dilmer.)

Wilmer, 33, and Demi have been on and off since first hooking up in 2010, not long after her split from Joe Jonas. In the years since, Valderrama has been publicly linked to Minka Kelly, while Lovato was reportedly seeing One Direction’s Niall Horan. Back in February of this year, sources said the off-again couple was very much on-again.

That same month, the ‘X Factor’ judge did an interview in which she spoke philosophically about romance.

“I am in a place where I can finally trust and love and be a better person for the man who I am in a relationship with, instead of being a clingy girlfriend or getting jealous,” she told Cosmo on Campus (quotes via MTV). “It is very unhealthy when girls devote all of their time to a guy and forget their friends and family. I did that. I was always looking for distractions because I was so afraid of being alone.”

The couple at a wedding of their friends, Tiffany Thornton and Christopher Carney.