NORWALK — Two women — one a 49-year-old hairdresser living with her unemployed boyfriend and another man in a one-bedroom trailer; the other a 33-year-old waitress helping her hapless father put his life back together — both killed by the men they supported.

Domestic violence experts say that abusive behavior can run the spectrum of relationships and situations as part of a systematic pattern of power and control perpetrated by one intimate partner against another.

“There is violence toward women in all strata,” said Marielynn Herrera, coordinator of Stamford-based Domestic Violence Crisis Center. “It all goes back to power and control and it’s hard to break away. When an abuser doesn’t have the ability to have power, they lose control.”

The case of Melissa Wilkinson, who was killed early Monday morning by her 55-year-old father in an apparent murder-suicide, could be described as somewhat unusual in that the alleged abuser held no financial power in the relationship.

But financial power can take on multiple forms, Herrera said.

“The victim can be manipulated to spend money to provide for their purposes and they may manipulate the breadwinner for financial reasons,” she said.

Police say Mark Wilkinson had been sleeping on his daughter’s couch for the past two years before he shot and killed her and then turned the gun on himself hours later following a stand-off with police.

Wilkinson, who had a history of arrests for drunken driving and weapons charges, had recently lost his home and business. His daughter had been allowing him to stay at her apartment, but on Sunday had told him it was time to move out.

Just five days earlier, on April 26, 59-year-old Paul Bjerke was charged in the fatal assault of his girlfriend.

In what may be seen as a non-traditional living situation, Lisa Zemlok was found dead in the sole bedroom of a Westport Avenue mobile home that she shared with Bjerke and her ex-boyfriend.

Police have called the assault “domestic in nature” while court records describe a patter of abuse that culminated in Zemlock’s death.

According to court records, the woman’s ex-boyfriend arrived home around 1:30 a.m. to find Bjerke “drunk on the couch watching TV.”

The ex-boyfriend found the woman dead in a locked bedroom and called police. He later told police that Bjerke is often abusive and that “he starts trouble when he’s drinking,” court records show.

Karen Jarmoc, CEO of the Connecticut Coalition Against Domestic Violence, said both cases represent the varying dynamics of domestic violence.

“We primarily work with victims of domestic violence, but there is a different dynamic between father and daughter,” Jarmoc said. “What I can say is that when there is conflict within a family, emotions can run high. When that occurs those stressors can cause bad outcomes.”

Jarmoc said that having access to a gun increases the likelihood of such an outcome.

“Studies show that having access to firearms increases the chance of homicides by five times in domestic situations,” Jarmoc said.

Those figures are from the Connecticut Coalition Against Gun Violence, which stated that “firearm use accounted for the murder of 100 women in Connecticut from 2002 to 2011.”

According to FBI crime reporting statistics, in 2014, nearly 29 percent of homicide victims were killed by someone they knew other than family members, (such as a neighbor, friend, or boyfriend), 14.3 percent were slain by family members, and 11.5 percent were killed by strangers.

Of the murders for which the circumstances surrounding the crimes were known, 40.4 percent of victims were murdered during arguments (including romantic triangles), according to the FBI.

Jarmoc stressed the importance of bystander intervention in averting tragedy.

“People who are in a bad situation don’t always view things as bad as they are,” she said. “In any type of living circumstance when someone you live with is emotionally disturbed, we recommend getting help before it becomes fatal.

“People who are around the situation — neighbors or family — should report the situation,” Jarmoc said.

The DVCC is the only domestic violence agency serving the cities and towns of Stamford, Norwalk, Westport, New Canaan, Darien, Wilton and Weston. To report an incidence of domestic violence, contact the DVCC hotline at 1-888-777-2900. Spanish-speaking counselors are available.