Wilmer Valderrama has called his relationship with Demi Lovato "beautiful".

Wilmer Valderrama

Wilmer Valderrama

The 35-year-old actor has been dating 23-year-old singer Demi for the past few years and the pair are happier than ever.

Opening up about their romance while attending the opening night of Jennifer Lopez's residency at Planet Hollywood in Las Vegas on Wednesday night (20.01.16), Wilmer spoke about the secret to their happy union.

Wilmer said: "You know, we've been best friends for about six years. We haven't necessarily been dating for six years, but we have six years of friendship, and it's been ... it's been beautiful.

"All I did was love her exactly when she needed me to love her," he added. "And you know, we just stay honest. That's it."

Demi has previously spoken about how Wilmer supported her when she went to rehab.

She told Cosmopolitan magazine last year: "We started dating when I turned 18... Right after that, I went to rehab. People told him, 'You should probably leave. She's on a spiral, and you're going to be sucked down with it.' But he was like, 'I'm not leaving. This is somebody I really care about'. We relate on a lot of levels. I've seen a lot of s**t. S**t people don't know about."