In last night's episode of TOWIE, Bobby called time on his relationship with Harry after admitting the trust between them had gone.
During the cast trip to Marbella in June, Bobby discovered that Harry had been speaking to his ex - and had slept with him one week into their relationship - and Barry are unable to come back from the revelations.
However, hours after the split, Gemma attended a BBQ at Harry's family home (having made up from their recent epic row) and Bobby is not impressed.
Speaking in an exclusive video on the official TOWIE website, Bobby said: "Literally, the day I break up with Harry, she's gone round his house and had a BBQ with him and his mum, which I just find a little bit strange.
"I know she's in a really hard situation being friends with both of us, but considering Harry and Gemma have been rowing for weeks, I find it quite strange she's gone round there."
Bobby continued: "I am feeling betrayed by Gemma. I feel like her loyalty to me isn't as great as it is with Harry unfortunately.
"I feel like she values his friendship more than she does mine, which is really sad actually."
Bobby and Gemma first came to blows in last night's episode during a fashion show, held by Lauren Pope and TOWIE newbie Vas J. Morgan.
"Gem, why are you going round his house?" Bobby asked her. "I split up with the boy this morning by this afternoon you're round there toasting - ching, ching - and eating his garlic bread.
"You've gone back round there and you're back on Team Derbidge."
Defending herself, Gemma replied: "I have fought your corner the whole way. If anything, I sat there and explained to the family why we were so angry with them. I believe there is a break-through here."
But Bobby shot back: "The only thing that's here is you going round eating cheeseburgers, Gem. I think it's f***ing out of order.
"Where's your loyalty? You need a moral compass. I've had your back through everything. You're round there eating his boiled egg salad. I'm f***ing devastated!"
Oh dear! (Although it sounds like it was a tasty BBQ)
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