Keisha Buchanan believes the Sugababes will struggle without her.
The singer – who was replaced in the group in September by Jade Ewen following a series of rows with her bandmates Heidi Range and Amelle Berrabah - insists the current line-up are only out for themselves and she doesn't miss their friendship.
She said: "I'm doing what's best for me. They did what's best for them.
"The fact is, I was in Sugababes for 12 years. I was in that band because I loved it, not to elevate myself.
"I did a lot of stuff behind the scenes for the band that people don't know about. I was always the one working hard."
The 25-year-old star also denied reports she is planning to reunite with fellow original Sugababes Mutya Buena and Siobhan Donaghy, insisting she is happy to be a solo artist.
She added to Britain's Daily Star newspaper: "You've got to move on and I've got Mutya and Siobhan supporting me now.
"I didn't have any plans to go solo. It was all really sudden so it's taken me a while to adjust. I love just being in the studio.
"I haven't got a release date just yet, but I think it's really important that I get it just right."