Nikki Sixx's stories about his drug years have been called into question recently, but we're inclined to give his memory the benefit of the doubt -- after all, he certainly hasn't forgotten his grudge against Godsmack singer Sully Erna.

The beef between the two stretches back to Godsmack's 2010 single 'Cryin' Like a Bitch,' which is said to have been sparked by Sixx's less-than-friendly behavior toward the younger band when they toured together during the 2009 Crue Fest. Erna stoked the rumors when he discussed the inspiration behind the No. 1 Mainstream Rock hit during an interview with HardDrive Radio, saying, "I have never been in a situation where I felt like I was out for blood, and honestly, this was the first time that I felt like: 'You know what? If there's gonna be some people that are gonna treat other people a certain way, then I'm gonna go out there every night and f---ing crush you on stage -- make sure that we make you look old and fat, and go home with a nice big fat paycheck. You can sit in your world and I'll sit in mine, and see you at the top again, I guess, somewhere ...' I don't know. All I care about, really, is playing music and enjoying myself on the road. I'm not here to compete. Everybody has their fans, everybody has their own music, and it's supposed to be more like a brotherhood, but ... I don't know."

Although Erna has refrained from directly admitting Sixx was the culprit, he's close with Crue drummer Tommy Lee, who later laughingly admitted: "I think he just had some issues with the way he was treated by somebody else in the organization. But I'm gonna stay right out of that."

Sixx didn't find the humor in it then and he's still not amused now, judging from recent remarks he made alleging that Godsmack reached out in an effort to promote its upcoming album on his 'Sixx Sense' radio show. Tweeting that the band "begged" for a guest spot, he cracked: "Good luck touring phonebooths. Whos [sic] crying like a bitch now?"

He offered an in-depth explanation of the tweet during a subsequent episode, saying: "Yesterday, somebody came into the studio and they said, 'Hey, Godsmack would really like to be on this show.' And I said, 'Over my dead [expletive] body.' And they said, 'Well, you know, they wanna be on the show because their record's coming out.' And I go, 'Did you forget the fact that they wrote a song about me called 'Cryin' Like A Bitch' and that there's probably 15 festivals that Motley Crue is headlining and that we said if Godsmack's on 'em, we're not doing them? And that was just the beginning of my revenge. And that I take every opportunity to slander them and be very immature? And then they wanna be on the show? Dude, have some credibility. I mean, Jesus Christ! I'm so embarrassed for you. At least you can go, 'We've got a new record and we don't wanna be on that [expletive]'s radio show.' [And he said], 'Well, we actually need some help now.'"

Funnily enough, according to Godsmack drummer Shannon Larkin, it's really San Diego Chargers quarterback Philip Rivers who should be upset. As he told Static Multimedia: "I came up with the title 'Cryin' like a Bitch' after seeing [Rivers] crying on the sidelines after a loss. That may sound cruel, but hey, I'm a Raiders fan. 'Nuff said."

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