Don't be embarrassed about the CID thing. I thought they were the police detectives, but I had to look it up to check. Depending how it was said to you I can see how it could easily sound like a completely separate organisation.
MARAC sounds like it could be helpful (below) in handling contact with your ex going forwards, though it doesn't sound like you would attend.
Did they mention any counselling options? If they don't offer then perhaps you should ask, or you could make an appointment with your GP, explain what's been happening and ask to be referred for counselling.
'What is a MARAC?
MARAC (Multi-Agency-Risk-Assessment-Conference) is a meeting where information is shared on the highest risk domestic abuse cases between representatives of local police, health, child protection, housing practitioners, Independent Domestic Violence Advisors (IDVAs) and other specialists from the statutory and voluntary sectors. A victim/survivor should be referred to the relevant MARAC if they are an adult (16+) who resides in the borough and are at high risk of domestic violence from their adult (16+) partner, ex-partner or family member, regardless of gender or sexuality.
After sharing all relevant information they have about a victim/survivor, the representatives discuss options for increasing the safety of the victim/survivor and turn these into a co-ordinated action plan. The main focus of the MARAC is on managing the risk to the adult victim/survivor but in doing this it will also consider other family members including any children involved and managing the behaviour of the perpetrator. Information shared at the MARAC is confidential and is only used for the purpose of reducing the risk of harm to those at risk.
At the heart of a MARAC is the working assumption that no single agency or individual can see the complete picture of the life of a victim, but all may have insights that are crucial to their safety. The victim/survivor does not attend the meeting but is represented by an IDVA (Independent Domestic Violence Advisor) who speaks on their behalf. Consent of the victim/survivor is preferred but not compulsory for a MARAC referral to be made. The Perpetrator of abuse should not be informed of the MARAC Referral.
Cases are referred for a one-off discussion at a MARAC. The MARAC is not an agency and does not have a case management function. The responsibility to take appropriate actions rests with individual agencies; it is not transferred to the MARAC. When referring to the MARAC staff should continue to work with the victim/survivor to reduce risk and make appropriate safeguarding referrals.'