Ex-girlfriend details alleged abuse & 'mood swings' by VTA shooter, per court docs

Court records detail a troubling relationship between the man accused of killing eight people at a San Jose VTA facility and his former girlfriend.

The filing from 2009 offers a window into the mind of 57-year-old Sam James Cassidy, whose attack on Wednesday morning became the latest mass shooting tragedy in the Bay Area, prompting the obvious question: Why did he do it?

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Cassidy then killed himself as law enforcement descended on the scene Wednesday.

 His ex-girlfriend outlined shocking allegations while responding to a restraining order he filed against her more than 10 years ago. 

In a phone interview, KTVU spoke with her on the condition that she not be identified. 

She said while she thought Cassidy was mentally unstable, she never expected him to set his home on fire before killing nine people at his workplace before ending his  own life

"I feel shocked," she said. 

SEE ALSO: San Jose VTA shooting kills 10, including employee who opened fire

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She said they met online in 2008 and only dated for months when he proposed to marry her and asked her to move in with him. Their relationship ended 12 years ago, and she wants to forget that part of her life. 

"He had a double personality," she said. "He could be a gentleman." 

But she also said he could be a jerk. 

"When I was dating him, he was mentally up and down," she said. "He hurt me so much. I got hurt, you know." 

Ultimately she turned his offer down and said it was too soon. After that, she said he became mean and violent. She said he complained about his co-workers and bosses when she knew him. 

He worked at VTA as an electrician and he complained about his co-workers and bosses.

"He said they were mean to him. Too much work, too stressful. I feel bad. I feel sorry. It's so crazy, right? He killed so many people. I feel sorry for the people who died." 

She said she dated Cassidy for about a year, during which he "exhibited major mood swings as a result of bi-polar disorder." 

Those mood swings only grew worse when he was drinking alcohol, she said. 

"Several times during the relationship he became intoxicated, enraged and forced himself on me sexually," she wrote in the filings.

 She said at times she did not want to have sex with him and he "restrained me by holding my arms to my side and forcing his weight on top of me."

What's more, the ex said Cassidy "attempted to force anal sexual intercourse" and she would fight him off and refused every time.

The two later fought over a roommate who had apparently moved into Cassidy’s home at 1178 Angmar Court where he previously lived with his ex-wife. That home was being investigated Wednesday after it was apparently set ablaze before the shooting.

Evan Sernoffsky is an investigative reporter for KTVU. Email Evan at evan.sernoffsky@foxtv.com and follow him on Twitter @EvanSernoffsky