Morgan & Anna - History

This is what I have been able to learn about Anna and Morgan's relationship:

Anna Hendricks and Morgan Shane had been best friends since the age of eleven, when Morgan and her mother moved to Fresno from Carson City, NV after her parents' divorce. Anna was born and raised in Fresno and the two met at Rio Vista Middle School. They had been virtually inseparable since.

One glimpse of their
social media pages confirms this.

They attended Sunnyside High School together and remained just as close throughout their teenage years. It is not surprising that they planned to attend the same college, so both applied to Colfax and were accepted.

As the video clips reveal, their friendship began to fray during the two months prior to Anna's murder, but IMO this is just more evidence supporting my theory. How can anyone believe that, after eight years of a friendship that was closer than most sisters, their relationship could crumble -- in just two months -- to the point where Morgan would actually murder Anna.

It makes no sense whatsoever and points to "external" forces as the inciting cause.