SAN JOSE, Calif. (KRON) — Whatever it was that led VTA maintenance man Sam Cassidy to murder his coworkers appears to have been brewing for some time.

So says someone who lived with him for 10 years — his ex-wife.

“I was getting to the point where I was starting to feel kind of unsafe at times.”

Cecelia Nelms says the murderous rampage committed by her ex-husband Samuel Cassidy has left her in shock.

“He has a temper. Everyone has a temper,” she said. “But I just can’t believe he did this.”

Nelms and the 57-year-old Cassidy divorced in 2005 after their 10 year marriage began to unravel.

“He would scream and yell at me to intimidate me,” Nelms said.

Nelms says Cassidy suffered from bouts of depression.

She does not recall hm making any threats and is struggling to come to terms with the fact that the man she fell in love with shot and killed nine of his coworkers at the VTA rail yard in San Jose.

But she says even back then, Cassidy was not happy at work.

“He would talk about some people don’t do much, some people slacking,” she said.

Nelms says there were good times too, like when he surprised her with a trip to Puerto Vallarta and at her sister’s wedding.

As his mood swings worsened, Nelms grew worried as Cassidy would vent his anger on the walls of their San Jose home and was verbally abusive. But she does not recall him owning any firearms.

“Not at all. I never knew that side of him liking guns,” she said. “Not even talking about it.”

Nelms had not spoken with her-ex husband in 15 years.

She believes his depression got the better of him and as his mood swings got worse, tending toward violence, although none directed toward her, she knew it was time to go.