According to The Sun, Chantelle announced the split on Twitter, writing: "Unfortunately I have had no option but to end my relationship with Alex."
Earlier this week cage fighter Alex was arrested on suspicion of causing criminal damage while forcing entry to the Essex house, but was later released without charge.
In an interview with this week's New! magazine, Alex hinted that at trouble between the pair.
Asked if he had thought of splitting from Chantelle, he said: "It crosses your mind, and I don't feel bad about that.
"You think, 'Would this be easier if we weren't together?'"
But he insisted: "I love her to pieces. I want to be with her."
Chantelle and Alex welcomed their daughter, Dolly, to the world in June.
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