This is from an interview with Nikki DeLoach of the girl group "Innosense". And yes, rumors DO SUCK!

What really caused you and JC to break up? Rumors suck! We need to know the truth!!
Rumors do suck!! LOL. Well, even though I know JC loved me very much, there had been some things that he wasn't completely honest about. I broke it off after that & then we tried many times to get back together. But, it was just to difficult. We both did things that were not honest after our break up & once trust is broken, it is hard to get it back. You know girl!!

Hey, Nikki! First of all, I just wanted to say that I'm a big fan of yours and of Innosense. Well, I heard that during the filming of MMC, you and JC Chasez of *NSYNC were a couple. Is there any truth in this? And how long were you two going out?
Yes, JC and I did date on the MMC. We actually dated for about six years. We made a lot of great memories.