In last night's episode of TOWIE, Jon Clark claimed that Kate is 'sleeping with one of his friends.' He told Dan, after confessing to sending Kate voice notes asking her for a 'cuddle', and admitted he had kept it a secret, like Kate had asked, "for months."
Dan has now pointed out that he and Kate were still trying to work out whether they could rekindle their romance at the time, and admitted he's "gutted" to hear she had moved on so quickly.
In a new video shared to TOWIE's official website, Dan said: "I'm gutted to be honest, more so now because [Jon] has told me about the Kate thing. Although we weren't together, it was very soon after we split up and we were still deciding what we were going to do, whether we are going to split up or not.
"We were still speaking a lot. Up until Majorca we were still [working out] what we going to do. To hear that, yeah, it does hurt. She's single at the end of the day, so I've got to take it on the chain really. If that's how she wants to move on, then that's how she wants to move on."
Dan explained that he was more annoyed with Jon for lying to him about Kate seeing somebody else, when he'd had plenty of opportunities to tell Dan.
"I just felt like if [Jon] was coming round mine a lot, and spending a lot of time with me, the amount of times I have asked him about, he would have told me. The whole thing adds up now. Kate didn't tell me about Jon because she knew Jon had something on her. That was obviously why.
"I was thinking to myself the whole time, 'Why would Kate not tell me if one of my pals had messaged [her]?' Now Jon's told me that, it all adds up."
Dan added that it had been a "kick in the teeth" to hear Jon claim Kate has been 'sleeping with his friend', especially as Kate had accused him of sleeping with another girl following their break up.
Dan had denied doing so, telling his ex the rumours were "absolute b******t."
"I always feel like I've been accused of doing stuff and it comes out that all along, she has been seeing someone," Dan said. "Even though we've split up, me and Kate have still been very close... it's just a bit of a kick in the teeth."
Viewers saw Dan text Kate and tell her he needs to talk, suggesting that we will get to see how things unfold between the former flames on Wednesday's episode of TOWIE.
As for Jon, however, it sounds like Dan is finding it hard to forgive his pal. Dan explained: "I know he's admitted it and said sorry, but if he's done that then, how can I trust him not to do it again? It makes it very hard for me and him to be friends again."
Jon, meanwhile, has said he is "devastated" over letting Dan down and he's predicted that Dan won't forgive him for lying to him any time in the near future.
"I feel like absolute sh*t," Jon said. "He's supposed to be my pal. The way he was with me made me feel even worse. He wasn't even angry with me, he was just disappointed."
TOWIE continues Wednesday 10 August at 10pm on ITVBe.
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