Frankie, who left The Only Way Is Essex in 2014, was travelling on the train on Thursday afternoon when the unnamed passenger began "shouting and pointing" at his other half.
Horrified that no one was willing to defend the woman, Frankie stood up and confronted the man about his behaviour. She has since shared her experience on Twitter and described the culprit as a "bully".
Frankie told her followers: "Some nasty fella shouting and pointing this afternoon in his woman's face on the train! Everyone just sitting there until I stood up! #bully.
"Poor cow, just sitting there getting screamed at! What is going on in this world? I know, don't get involved, but if that was me I'd be praying that someone stood up and shouted, 'leave her alone'!! Makes me sick how some men treat women! #bigbully."
She added: "Makes my blood boil! RANT OVER #trainpeace."
Frankie has received a wealth of praise from her followers for coming to the lady's defence - and she does not regret her actions. Replying to one well-wisher, she said: "It's so bad! Imagine if that was your daughter? Can't cope with this world."
Well done, Frankie!
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