But the former Hollyoaks actress also said she still "loves him" and will "be there for him when he gets help".
Less than an hour after going on a Twitter rant, Steph shared six private Twitter messages, beginning on 29 March, allegedly thought to be between Jeremy and an Irish model.
The message exchange from Jeremy said: "I don't always see a girl I like on Twitter... I'm a loyal guy... I might have slept with a few people when seeing Steph but I wouldn't do it in a committed relationship."
The girl in question told him she had a boyfriend, to which he replied: "Shame you have a bf like I'd have taken you out, treated you like a princess that you are."
After sharing the screenshots, Stephanie said: "One mug I've been, thanks to my amazing friends! Onwards and upwards oh and that's 1 out of 9."
Jeremy has not publicly responded to the cheating allegations. Reveal have contacted both Steph and Jeremy's reps for comment.
Then, hinting that their relationship was definitely over, Steph said: "Broken! I said u love me sort it and apologise, too late now, I've been 100% faithful, hoe i said I'd never leave him and he hurts me like this. For all your information by his ficked up messages I have tried for two days but no getting through to him. I love him despite it all and will be there for him when he gets help [sic]."
She added: "Always a believe in love and still will love him. I will never forget you, words so true. Love u always, despite your ways. Broken."
Hints that their relationship is over for the fourth time comes after Steph's rant where she hit out at "lies". Meanwhile, Jeremy said he was turning over a "new leaf" as he favourited tweets from fans suggesting they had split.
This comes hours after Steph denied claims she had gone "AWOL" on Jeremy.
Reports claimed Jeremy had tried to get in touch with her after she had 'gone missing' while allegedly 'seeing another man'.
Steph, who fell in love with Jeremy in the CBB house earlier this year, slammed the accusations, saying she will always be "100 percent faithful" to him: "The biggest load of b*llox I've ever read!!! U enjoy trying to ruin people's lives?"
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