She chose Sheryl to accompany her on the task as she knew she was a nice person and ultimately a soft touch who would not expose her weakness to the rest of the contestents. She did not know what the task involved so if she was really interested in bringing food back rather than playing to her own agenda she would have taken Linford. An athlete up for the physical challenges who wanted to take part.

She should have chosen Jenny or Alison from the females or Shaun from the males.

They wouldn't have cossetted her or pandered to her "phobias" They would have shouted at her to get the f*ck on with it and get them some food, and when she failed they would have told the camp, in no uncertain terms, exactly how much she didn't try

She chose Sheryl because she was the least likely to detract from her camera time, and she was right. I doubt that she is really afraid of anything.

IMO she picked Sheryl because she has her down as a softie, who wouldn't go back to camp and tell the other campmates what an utter idiot she is.

Sheryl is not a sh*t stirrer and wouldn't be likely to go back and actually tell the other that GM doesn't try at all.