Make the first sentence usable
Lead with the reason for writing so the recipient does not have to decode a long emotional introduction. For a message about how to support someone leaving an abusive relationship, use this factual base: acknowledge the loss as they describe it and notice the immediate housing, childcare, work, or social impact.
Reduce the work of responding
Offer simple options, a narrow question, or a clear update that can be understood without another conversation. Offer one practical task or a form of company that does not require them to retell the story. Make the immediate next step clear enough that the recipient can answer without reconstructing the entire history.
Respect the boundary already visible
Do not attack the ex, push dating, demand details, or share the news before they are ready. For abuse, stalking, housing danger, child risk, self-harm, or immediate danger, connect them with specialist or emergency support. A block, explicit refusal, legal restriction, or safety plan takes priority over the desire to explain more.