What I've bolded is another good way to paraphrase what both
@CocoHusky and I noted regarding victims not seeing what's happening. Sometimes victims don't realize this until it's too late.
Maybe the phrasing we used generalized things, but from what I was taught in high school and afterwards, it was always noted that victims may not even realize what's happening as the abuse can get worse over time. I also have women's shelters as business clients, where some of their clients have been kind enough to share their stories where they've said just as much.
The link below is from the Mayo Clinic and noted this in the opening part of their summary:
"It might not be easy to identify domestic violence at first. While some relationships are clearly abusive from the outset, abuse often starts subtly and gets worse over time."
Domestic violence can happen to anyone. Understand how to break the cycle of abuse.
www.mayoclinic.org
It may not be data, but it's an American source that can be verified. Hope this helps.