Dragon Ball Super's manga has been in the midst of a tumultuous new battle for Goku and Vegeta as Planet Eater Moro has seemingly defeated them at every turn. Not only does he get stronger with each new chapter, he's gotten back his magical power, made three successful wishes on the Namekian Dragon Balls, and he's beaten both Goku and Vegeta at several occasions throughout the arc so far. It's probably a frustration situation for the Saiyans who usually power through.
It seems that enough is enough for Vegeta at the end of the latest chapter of the series as when the battle with Moro forces Goku and the others to retreat, Vegeta instead parts ways with Goku and the others and chases down Moro instead.
In Chapter 50 of the series, the battle with Moro has reached a terrifying new phase as it was revealed that his third wish was to free all of the other prisoners still being held in the Galactic Prison. When they arrive on New Namek, Goku and Vegeta suddenly find themselves at even worse odds when Moro devours their Super Saiyan energy once again. This forces all of them to retreat, and when Goku wants to Instant Transmission away, Vegeta refuses.
Frustrated, Vegeta exclaims, "Stupid magical spells, stupid God power, forget Instant Transmission!" Shouting that the Saiyans have always prided themselves on their physical might and power, these tricks are beneath him and this fight full of twists and turns is beginning to frustrate him. He hates how he's been reduced to this helpless and ridiculous state, and thus decides to chase after Irico's Galactic Patrol ship.
Saying that this is where he's parting ways with "you people," the end of Chapter 50 sees him in Irico's ship and threatening to blast him unless they go to where he wants. It turns out he wants to go to Planet Yardrat, which fans will remember as where Goku learned the Instant Transmission technique before the Android arc.
Vegeta's been steadily getting frustrated with each chapter of the series, and it's not hard to see why as he's been belittled by Moro each time they battle. Even when Goku and Vegeta were confident that they'd win, they still lose thanks to those tricks. Moro is one of the first villains to have an intelligent plan up his sleeve rather than just display might and strength which as Vegeta says, the Saiyans usually overcome. But now it's just a matter of seeing what kind of plan Vegeta has up his sleeve.
Dragon Ball Super currently airs its English dub on Adult Swim during the Toonami programming block on Saturday evenings. It is also available to stream on Funimation and Amazon Video. The Japanese-language release of the series is complete, and available to stream on FunimationNOW and Crunchyroll. The manga has chapters that can currently be read for free thanks to Viz Media, and Dragon Ball Super's big movie, Dragon Ball Super: Broly, is now available on Blu-ray and DVD.