The 27-year-old star sparked the rumours after allegedly deciding to leave Heaton out of her new pop project with Jessica Taylor, another ex-member of the group.
Young and Taylor teamed up to form singing duo Danger Minx earlier this year and have since been writing their own '80s-style tracks.
Speaking to Take 5 magazine, Young insisted: "Michelle was fully aware of the project - but she's doing her own thing. She also lives in Ireland now as well, so it wouldn't have been practical.
"I'm really looking forward to the next step. It's all guns blazing for Danger Minx."
The pair have not yet landed a record deal for the venture but hope to secure a contract within the next few months.