The 25-year-old split from former TOWIE star Lewis, 27, earlier this year, after he was accused of being unfaithful, and since then she’s struggled with whether or not to take him back.
Now, Marnie has confessed she “wasn’t perfect” in the relationship either and some of her behaviour on the set of Geordie Shore may not have been pleasant for Lewis.
“Nothing has changed with Lewis. We’re speaking, but I still don’t know what to do,” she writes in her new Star magazine column.
“I love him, but I’m worried he’d cheat again.”
Marnie adds: “I wasn’t perfect either. I didn’t behave like a lady or an appropriate girlfriend when I was filming Geordie Shore, and that embarrasses him.”
Last week, Lewis admitted to kissing another woman during a romantic holiday with Marnie – but claimed Marnie had “humiliated” him by flirting with another man.
The star gave his side of the incident in Barcelona, and revealed he ended up kissing a girl on the beach after leaving his then-girlfriend asleep in their hotel room.
However, he has told The Sun Online that he was driven to being unfaithful after seeing Marnie flirting with an ex-fling she caught up with in the city.
“We met this guy who was very good looking and I was standing there very observant, I could tell there was some kind of history as she was all over him and wouldn’t stop flirting,” he said.
“We got into the cab to go back to the hotel and Marnie’s mates started asking who he was and Marnie says, ‘Oh me and so-and-so have always had a thing.’ “
He added: “Marnie just really embarrassed and humiliated me on our beautiful holiday over this very, very handsome guy that she had history with.”
Lewis admitted that it was “pathetic” to cheat, but claimed he did it not out of revenge, but because he felt emasculated.
However, Marnie has responded and denied being “all over” the man – and said she “didn’t deserve” to have Lewis behave how he did.
She told Mirror Celebs: “I bumped into someone I had kissed prior to meeting Lewis and I was a little tipsy by no means all over him.
“Maybe over friendly perhaps but certainly not all over over him. I have never cheated, wouldn’t cheat and didn’t deserve to be cheated on for this.”
Marnie Simpson heartbroken over Lewis Bloor’s cheating
Meanwhile, Marnie admitted last week she still loved Lewis.
“He’s apologetic and I know there are reasons why he cheated, but I don’t want to go into that. It’s not like he just went out and did it,” she wrote in her Star column.
“It’s hard to say if I’ll take Lewis back because I don’t know if I’m strong enough to forgive him. But I do still love him, even though he’s hurt me. I need more time to figure out my feelings.”