it's a very complicated matter. Beyond whether one has self esteem or not. And contrary to beliefs out there, it's more than whether they apologize and act sweet, usually they don't. There's financial, legal, spiritual, social, housing, kids, pets, etc as aspects.
Most shelters are book, women can lose custody if not abiding by visitation, or moving too far away. Most family of origins and friends of a battered woman, are reluctant to open doors. Churches don't really help, public housing has years of delay, child care vouchers take months to kick in(how does one pay that and rent, once out), the batterer can lose employment, where's the victims spousal/child support then? List goes on, wish I didn't know it this way, really wish i didn't know...