Mum-of-five Katie posted an unflattering picture of Jane to her YouGossip account alongside a caption referencing the affair.
A clearly still angry Katie said: "Whoops, Jane Pountney from Storrington who had sex for ten months behind my back whilst I was pregnant."
Katie also retweeted a meme sent to her from a fan.
The meme read: "I will NEVER understand how a woman could be okay with being 'the other woman'. If you pursue a married or a taken man you are nothing but a SLUT and a HOMEWRECKER."
Katie, 35, was left devastated in May when she discovered husband Kieran had been having an affair with her best friend Jane.
The affair started while Katie was pregnant with Kieran's son Jett and she claims Kieran and Jane even slept together while she was in the hospital after giving birth.
She learned of the affair just days after discovering she was pregnant with their second child, Bunny.
Katie vowed to divorce Kieran after learning of the affair but later decided to give their relationship another chance.
This is the second time Katie has lashed out at her former friend Jane in a week. She ended 2014 with a rant against her, proving that she has not forgiven … or forgotten.
"Hopefully last time I mention them to remind people they are biggest w***** in the world and wish them a s*** [...] life forever and no matter how sexy they tried to be... They lost the pricey win again ;)."
Katie recently showed how happy she is with Kieran by sharing a selfie of them laughing together over the holidays.
But she told Fabulous magazine: "I won't forgive him and I won't forget. But I love him and I'm sticking by him. This has been the most hellish, insane, vile year of my life, but I've come out of it a better, stronger and more determined woman."
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