Axl Rose Is NOT Dating Lana Del Rey ... Says Guns N' Roses Guitarist

4/9/2012 9:00 AM PDT

If Axl Rose and Lana Del Rey ARE dating, it's news to Guns N' Roses guitarist DJ Ashba ... who tells us he's convinced the two are just friends ... even though they left the Chateau Marmont together this weekend.

As we previously reported ... 50-year-old Rose and 25-year-old Del Rey piled into the same SUV and took off together late Friday night ... instantly igniting relationship rumors.

Despite the evidence, Ashba tells us, "I don't think they're dating" ... but he does offer up a pretty good explanation about why Axl would want to spend some private time with Lana.