It first started like this when the reverse Flash killed Barry mother (Nora Allen) 14 years after he gets struck by lightning and mixed with chemicals and in 9 months he became the FLASH so he used his powers to save Central city. And also to find the man who killed his mother. In some of these episodes Ronny who is Caitlin fiancee was joined to Martin Stein and they formed firestorm and they were separated not knowing that everything Ronny does that Stein will also do, so the military captured Martin and Flash and Ronny decided to save him then firestorm became one.So he found the man and he’s name is REVERSE FLASH also known as Eobert Thawne. He tracked him down and captured him so Barry decided to go back and save his mother. He went back but didn’t save his mother. So a black hole opened and Eddy Thawne Reverse Flash’s ancestor shot himself and reverse flash was erased from existence. So Eddy was sucked into the black hole. A singularity opened and was sucking the whole of Central city. So Barry ran into the singularity and was running in circles to stable it so firestorm separated in the eye of it and Ronny was not to be seen again.