Late to the party here, but I thought it was great. Erin Doherty was extremely good. She is 30 this year so I took it that the whole group was meant to be that age. As far as I could make out, Chloe had been attending either a state school in a middle-class area, or a private school, but for financial reasons she had to leave that school and go to the bog standard comp that Becky attended. Then her family's fortunes recovered and she moved to another posh school for the sixth form and made a new group of friends. She loved Becky but she was weaker and more easily manipulated than Becky, so when her new friends laughed at the idea of Chloe having a friend from the old crap school she went along with it and told her mum to ring Becky's mum and say she didn't want Becky to come round any more.
I've been fortunate not to experience a controlling relationship but I am an obsessive listener to The Archers, and quite a few of the same or similar devices were used here as in TA a few years ago when they had a storyline over years showing coercive control building up over a long period.
Putting the little woman down in front of friends - he did that when she dropped his phone and the screen cracked and he told them all that she didn't seem to have great spatial skills.
Sniffing her hair for chlorine when she said she'd been swimming. Constantly ringing to find out where she was and then checking whether she was telling the truth. (The fact that she wasn't is besides the point!)
Insisting on driving Becky's car for all sorts of spurious reasons and leaving her dependent on him for transport. Clearly he had chosen a house in a rural area and then manipulated Chloe into not driving by telling her that she couldn't safely drive because of her antidepressants, which she actually wasn't taking, but Elliott didn't know that.
Gaslighting her by pocketing her keys and then putting them back in a place she said she'd already looked.
He was manipulating all the friends too, into believing that Chloe had said things which she hadn't, and to get her to believe that they'd said things they hadn't, all of which isolated her more and more. He'd probably convinced her that she wasn't up to holding down a job. Very odd otherwise for such a young woman with no children not to be working.
Phoebe Nicholls was thoroughly unlikeable as Elliott's mum, reprising her turn as Rose's loathsome mother in Downton Abbey. She's come a long way from the sweet little sister in Brideshead Revisited! I wonder what had happened to Elliott's husband.