I think this Guardian article makes some important points:
www.theguardian.com/law/2020/feb/16/barristers-warn-of-strain-on-defendants-caroline-flack-death
'The Crown Prosecution Service has recently been under pressure not to drop domestic violence charges even when complainants withdraw allegations.....
Flack’s death comes amid a debate over the handling of domestic violence cases by severely understaffed police and prosecutors. There have been frequent criticisms of how the justice system allows manipulative partners to deter victims from giving evidence against them in court.
The charity Women’s Aid estimates that only between a fifth and a quarter of domestic abuse victims ever report attacks to anyone in authority.
A criticial report by Her Majesty’s Crown Prosecution Inspectorate (HMCPSI) last month urged police and prosecutors to improve their development of “evidence-led domestic abuse prosecutions” where “the victim is unsupportive”.
It said: “If cases can be built without over-reliance on the victim or complainant, then it is still possible for the prosecution to proceed when the victim either does not engage from the outset or is initially supportive but withdraws their support at a later stage in proceedings.
“In some domestic abuse cases, there will be enough other evidence that the prosecution need not rely on the victim’s evidence. Police officers and prosecutors are expected, wherever appropriate, to prosecute cases based on this other evidence.”