During the argument , Sanders informed Theresa that he was leaving her .
On July 6 , 1964 , the day after Sanders ' birthday , the couple were arguing because Sanders had spent his birthday out with friends instead of at home .
During the argument , Sanders informed Theresa that Sanders was leaving her .
On July 6 , 1964 , the day after Sanders ' birthday , the couple were arguing because Sanders had spent his birthday out with friends instead of at home .