@cnn: For years, Sandra Birchmore and Matthew Farwell exchanged thousands of text messages. The last one she sent invited him into her apartment. Now, some 40,000 messages recovered by investigators are key evidence in Farwell's trial for Birchmore's murder, with prosecutors and the defense using them to present sharply different accounts of their relationship and Birchmore's death. Farwell has pleaded not guilty. 📸: Sandra Birchmore, United States Attorney's Office