Viewers of last night's episode saw Lockie confessing to Danielle that he'd slept with three girls before they were an official couple – and that he'd exchanged texts since.
His admission came after he initially denied any wrongdoing when rumours of infidelity began to swirl around Essex.
Now, he has apologised, tweeting: "Cheating is inexcusable & destroys a partners confidence, for that I can only apologise & know that I've been a coward!! #TOWIE."
Viewers saw Danielle dump Lockie in a recent episode after struggling to cope with the rumours and being angry about a shirtless photo of Lockie standing next to a glamour model that was doing the rounds.
Last night, they came face-to-face, where Lockie finally admitted what really happened…
"Before we were official, I did sleep with some girls. Like, three girls. I can't justify it… I don't think it's right I think it's wrong. I'm trying to let you know what's going on in my head. I kind of panicked, I didn't want to fall in love with you."
He added: "When we were official, I haven't cheated on you but I have text, which is a form of cheating. Text and tweeted but I haven't slept with anyone."
Lockie's made no secret of the fact he wants to win Danielle back – and she recently admitted that although she's hurt, she can't stop thinking about him.
What's going to happen? Will they remain separated? Will Danielle forgive him?! TOWIE continues Sunday night on ITV2.
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