PEOPLE confirmed on Thursday that the couple have split after being together for just over a year

Inside Blac Chyna and Rob Kardashian's Split: She Became 'Super Fed Up' with His Issues, Says Source

Rob Kardashian and Blac Chyna‘s split was fueled by insecurities in the relationship, an insider tells PEOPLE.

PEOPLE confirmed on Thursday that Kardashian, 29, and Chyna, 28, have ended their year-long relationship and engagement. “They split a while ago. The wedding plans are off,” a source close to Kardashian told PEOPLE. “They are both trying to be mature about it. It was less dramatic this time.”

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Although the couple attempted to make their relationship work, the insider tells PEOPLE that Chyna became frustrated with Kardashian over time.

“Chyna is super fed up with Rob and thinks he is way too emotional and depressed. She thinks he has terrible issues,” says the insider, who knows both Chyna and Kardashian. “He is always battling his own insecurities and is unstable. It’s a major turn-off to her, and she thinks it’s incredibly unhealthy for the baby and their family.”

Just last week, PEOPLE reported that the mother of two was seen out to lunch with Jamel Davenport, a guy she was spotted getting close to during a Super Bowl party at Estrella’s MA Theater in West Hollywood last weekend, without her engagement ring.

“They’re living separately and she’s keeping Rob at arm’s length, both from the baby and from her,” the insider adds.

RELATED VIDEO: Inside Blac Chyna and Rob Kardashian’s Split — She Became ‘Super Fed Up’ With His Issues, Says Source

The former couple, who who went public with their relationship in January 2016 and got engaged in April, have had a complicated relationship, filled with ups (like the birth of three-month-old daughter Dream Kardashian in November) and downs throughout their year together.

But in recent weeks, the two appeared to be happy in their relationship, and showered their social media feeds with love for one another — spending New Years Eve together and celebrating their anniversary together with a sweet Instagram video that showcased home footage of the couple kissing, cuddling and laughing throughout their year-long relationship.

Last August, Kardashian exclusively told PEOPLE that Chyna got him through his “darkest times.”