I've heard of Tender Mercies Ministries, but not sure that is the same. I thought it was for recovering alcoholics. Maybe they've broadened their scope. Anyway, sometimes people who work in this type of service field find themselves in danger because some of the people they serve are unstable. I remember a homeless advocate who was murdered by a homeless man, for one.
It could be that someone she tried to help was looking for drug or alcohol money. Did she maybe talk to her son about signs of an attempted burglary, or report to him about some missing money?
Whoever has no rule over his own spirit Is like a city broken down, without walls. - Proverbs 25:258