I've just finished watching this now, and have caught up with the thread.
I'm shocked at some of the more critical posts about Caroline. She was clearly going through a crises after an extremely painful relationship break-up and made a questionable, impulsive choice getting together with Sandy. And then I think her head just got completely wrecked.
The smarmy, sneery "friend" did mention that she would previously never have touched drugs, and that her home was always immaculate, so that is evidence of her mental deterioration.
Yes the constant filming, filters etc may bit odd and make her seem less likeable, but that is irrelevant.
What is relevant is that thanks to her, a family have closure about their loved one. No-one in that cowardly community was going to put their neck on the line to bring the twins to justice, clearly.
I can see why she stayed with him - firstly, she was in a hell of a position, having to grass up a man capable of really scary, lethal behaviour. I can totally see why appeasing him and allaying his suspicions by staying with him seemed in her stressed state like the easiest option. Also, that "in love" feeling" is a hell of a drug, and that would have been a factor.
Either way, she wouldn't have known the location of the body had she not continued her relationship with him.
The police were appalling towards her, no care for her, and actively endangered her on more than one occassion (the policewoman at the flat, telling a friend of the twins about the Red Bull can). The blame for her non-appearance in court lies mainly with them.
I also think the "friend" had been in love with her, not the other way round, and was bitter at being friendzoned.
A lot of the internet's reaction to her is, as ever, expecting women to be the perfect victim. Her perceived flaws have been more harshly critisised than Sandy's reckless, callous actions. Bottom line though, Tony Parsons was returned to his family, Sandy and Robert were punished (yes the sentences were too short), and that was thanks to her, and she absolutely wrecked herself in the process.