Last month, three-fifths of the Spice Girls reunited to celebrate the 20th anniversary of their breakout hit “Wannabe.” It was cool to see Scary, Baby, and Ginger together, sure, but Victoria “Posh Spice” Beckham and Melanie “Sporty Spice” Chisholm’s mysterious absence left fans wondering: What happened to “friendship never ends?!”

In a new essay for Love Magazine (accompanied by a very ~sporty~ spread), Chisholm, a.k.a. Mel C, explains why she opted out of a new Spice Girls reunion tour. The singer — who’s now 42 and the mother of a 7-year-old daughter — says she didn’t feel right about doing a reunion without the whole group present. Beckham had already decided not to participate so she could focus on her family and fashion career, and Chisholm ultimately decided she’d have to bow out as well.

“The hardest part for me was letting people down, the girls, the fans, civilisation?!,” she wrote. “Unfortunately something didn’t feel quite right and I had to follow my gut ... We were a five-piece band. Anything less than the full line-up just didn’t feel like we’d be doing justice to the band or the fans.

“Look, I will be a Spice Girl until I die,” Chisholm continued. “But is it a new rule that bands have to reform? Why can’t we just be remembered for our incredible achievements in the nineties?”

Indeed, Chisholm appears to be done with the Spice Life, and says she sees the group’s performance together at the 2012 London Olympics as a perfect last hurrah.

“I’d love to play huge arenas across the world, sing our brilliantly bonkers pop songs and relive our former glory,” she wrote. “It is of course a very lucrative opportunity too. But didn’t we reach a peak with the Olympics? There’s a lot to be said for bowing out on a high note.”

She’s probably right — but that doesn’t mean it stings any less. Cue up the music: