Demi Lovato is ''grateful'' for her boyfriend.

The 'Cool for the Summer' hitmaker has gushed about her 35-year-old lover Wilmer Valderrama, who she has been dating for the past five years, for always being ''extremely supportive'' of ''everything'' she does.

She said: ''We don't share everything with the world. But we do feel comfortable to share a lot. With Wilmer and I and our relationship, he's extremely supportive in everything that I do. He makes me feel confident and beautiful. And I'm just really, really grateful for him.''

The singer - who celebrates her 23rd birthday today (20.08.15) - continued to say as well as Wilmer, she always surrounds herself with ''good people'' who are uplifting and positive.

She explained: ''You just have to surround yourself with people that are going to lift you up spiritually. That's what I do. I surround myself with good people and really rely on others for strength whenever I need it.''

Demi - who is currently working on her fifth studio album - added she thinks her new music reflects her mature outlook, reflecting how both herself and her fans have changed as they've grown up.

She told UsMagazine.com: ''I think my new music is definitely grown up. My music is definitely a lot more confident, sexier, and it's pretty much moving in that direction and embracing who I am as a woman.

''It's about growing together with your fans. Ultimately when you make music it reflects your life and I'm a lot older now so of course it's not going to be about the same thing I was singing about when I was 16 or 17.''