Viewers of the ITV2 show saw Bobby in tears at the end of yesterday's Marbella special after suspecting Harry of getting close to an ex-boyfriend while on a previous holiday to Tenerife.
Bobby found messages on Harry's phone and outright asked him what was going on. Harry said he did have dinner with his ex but swore that was it. Bobby, however, didn't seem convinced.
Speaking to the official TOWIE website immediately after the row, a devastated Harry said: "What has happened between me and Bobby is awful. It's the worst thing that's ever happened to us in the whole seven months that we've been together.
"I've moved on, I'm with Bobby. I will win Bobby back one million per cent because we're better than this. I love him so much. I won't let him go nowhere."
Harry suggested that someone in Marbs had been "stirring the s**t" that fuelled the row.
Earlier in the episode, viewers saw the couple's mutual friend Gemma Collins revealing that Harry had been coming to her for advice on the romance, which put her in an awkward situation as Bobby is her friend too.
Gemma also told Bobby that Harry's ex had been in Tenerife.
"Bobby has brought up about my ex-boyfriend which is absolutely ridiculous," said Harry. "I think Gemma basically planted into his head that I've been seeing my ex-boyfriend again and texting him which I haven't.
"I really couldn't care. I'm the sort of person who when they are serious about someone I'm a million per cent serious."
But despite Harry's insistence to Bobby - and the TOWIE website - a preview for next week's episode shows him telling Bobby that he did sleep with his ex.
WHAT?! Was this pre-Barry or while he was with Bobby?!
TOWIE continues Wednesday at 10pm on ITV2.
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