The `Skyscraper` singer - who recently split from boyfriend Wilmer Valderrama - says she`s too busy concentrating on her career and girlfriends.
She told Ryan Seacrest on his KIIS-FM show: "To be honest, right now there is no crush. I have a pact with my friends right now, literally no boys for X amount of days."
The 18-year-old star - who was admitted to rehab last November for three months to receive treatment for "emotional and physical issues" - also revealed how her personal problems means she and ex-boyfriend Joe Jonas are no longer close.
Demi - who appeared in `Camp Rock` with Joe - said: "He was my best friend for like years prior to that, so he knew about my problems. I mean when we first shot the first movie together."
When asked if Joe was there for her during her rehab stint, Demi said: "Yeah, I`ve had a lot of support, and you know obviously I`m not super close with him anymore just because a lot has happened, but I was very thankful to have the support of many many friends."