The 'Hero' singer - who has five-year-old twins Moroccan and Monroe with ex-husband Nick Cannon - called off her engagement to the businessman last month but insisted she isn't too heartbroken by the situation.
After talk show host Ellen DeGeneres noted how she was trying on wedding dresses in clips from her upcoming reality show 'Mariah's World' but they are no longer together, Mariah said: "Now it's a whole friggin' thing."
The presenter then asked how the 46-year-old singer was feeling and she replied: "I think I'm doing well...No, I'm actually...Everything happens for a reason. Things are the way they are."
But Mariah didn't seem to want to dwell on the subject and made an attempt to change the subject.
She said: "It's kind of difficult to talk about it at the moment.
"So, I'm just going to compliment you on these decorations once again because they are fabulous, and I am here, among them."
It was recently claimed the 'Without You' singer is "ready to move on" from James and feels relieved they never made it down the aisle.
A source said: "She's ready to move on. She feels like she dodged a bullet ... The negotiations aren't going well. At the best, she'll keep the ring."
The pair reportedly split after having an argument when they were in Greece.
A source said: "It started in Greece [with] some sort of outburst [from James] which everyone heard. [He told her,] I don't know if I can do this. I can barely take care of my own children."
And the couple failed to attend a planned meet up in Los Angeles back in October to "talk through everything as adults".
An insider claimed: "Mariah and James never met up after that. And they haven't spoken. The way the split news was handled was incredibly upsetting to her."