Three possible theories at the top of my list:
1) Strong armed robbery and abduction at the scene of her car. ( Highly doubtful)
2) The text was actually made by Cheryl as a stall tactic so her friend would go one without her. She was interacting with someone at her vehicle that nobody knew about. For whatever reason, this person and this meeting needed to be kept secret. Did this person know they were being kept secret ?
3) The entire scene was carefully staged. The text to the friend, the parking of the vehicle, the phone ceasing to function within minutes after the last text. It was many hours after that text before her husband called to report her missing. Also, if the husband had anything to do with staging all of this, how would he have been able to move around so much without being seen ?
I'm actually leaning towards theory #2. It fits the details at the scene. She vanished simply because she got into a vehicle with an unknown person after she parked her car where it was found. When and where her phone was disabled and what happened afterward is speculation. Her husband doesn't really seem to be the focus of police suspicions.......at least not yet.
Feel free to pick the theories apart, I'm open to revising them depending on the details which emerge.