Thanks to Seattle16. I was able to use her link to go directly to youtube to watch it. In my own words I'll share what I gathered from her interview and my own opinions.
I don't know what to make of the choking incidents because they sounded like they could have been more sexual that violent. I do think, if he tried that with the wrong woman, he would get a stronger reaction that he might term as "her starting to act weird". The ex gf admits she feels he could be dangerous, but she really didn't describe other dangerous scenes with him. They argued all the time towards the end, and he got ugly when he drank, but she didn't say he beat or choked her during those fights.
Ex gf did a fairly good job sharing what he was like to live with and didn't seen to sensationalize it needlessly. JC found fault with her often, and lectured her all the time. From what I understood she felt he seemed to enjoy hurting people or her by making her feel flawed or less. Sounds like he had a superiority complex and was controlling. She and even her family sometimes extended invitations to gatherings, but he never wanted to go.
How they met is they worked together, but I didn't catch where they worked. He was on probation for stealing a purse from a woman breastfeeding her baby. That is so low.