Caroline Elliot didn't do love at first sight. Aside from her boys (and possibly the house) there wasn't anyone who she instantly laid eyes upon and knew.

Caroline found warming to people so difficult that she'd spent the better part of her pregnancy with William worried that her child would be born and she'd feel the same indifference towards him that her father had always shown her. It turned out that she needn't have worried, and as soon as the warm, screaming bundle of tiny human was handed over to her, she knew she'd move heaven and earth for him.

But aside from people she had given birth to (and houses with perfect kitchens), someone had to prove themselves to Caroline before she regarded them as worthy of any kind of attention. So honestly, she didn't pay much attention to Kate McKenzie when the languages teacher first transferred to Sulgrave. She'd had a hand in hiring her, of course, but she'd seemed the most well-suited person for the post, and the following months proved that she was more than capable.

Like most people, it took a little while for Kate to worm herself into Caroline's heart. Initially, most of the conversations between the two, rather than sizzling with sexual tension, were brief functional exchanges during which Caroline was mentally making notes about the upcoming OFSTED inspection and planning a contingency for if John forgot to pick Laurence up from rugby. There simply wasn't time for anything else, and if she did happen to notice how particularly lovely Kate's hair looked that day, it was filed away in her brain for later, while she was brushing her teeth for bed and could shake her head despairingly at herself in the mirror.

Weeks and months passed in a frenzy of exam results, governor's meetings, funding issues. Then John dropped his bombshell and everything went quiet; a faint ringing in Caroline's ears and a little voice in her head telling her that she should have seen this coming.

And a louder one - her mother's - politely suggesting the same.

It seemed unfair, really. All the effort she'd been putting into running the school in the years up until now, and all it took was her husband walking out to discover she could actually do it on autopilot. She attended the meetings, made the decisions, but found herself caring less. She was torn between wanting to be emotionally available for the boys' sake – Laurence and his confusion, William masking his hurt with anger – and simply shutting her emotions out, as if pretending not to care would make it so.

A few weeks after Caroline had started going through the motions, she'd come to the languages department to find Kate to check in advance some of the dates for major performances of the student and staff choirs. It wasn't imperative that she attend, but she liked to, and it was irritating when important school events clashed. She'd tried looking for her in the staff room and the music department before seeking her out in the modern languages department and by the time she interrupted Kate's after-school marking, she was generally wishing she'd just sent Beverly. Rather than just walk in and demand the information, she'd appeared open enough to start a conversation, apparently, and a few minutes after Caroline's attention span had elapsed Kate was still talking.

"There's a bit of a paradox around the music scholarships, though, isn't there?" Kate continued, looking pleased that she could air her grievances directly to the headmistress, "students with a certain musical aptitude pay less, but they're the ones whose parents have been affording French horn lessons since they were six."

Kate looked at Caroline for any sort of input, then they both realised at roughly the same time that Caroline had been paying no attention whatsoever. Caroline tore her eyes away from where she'd been absently staring at the 'Saisons de l'annee' poster on Kate's classroom wall.

"Sorry Caroline, I didn't mean to bore you-" Kate's eyes looked so apologetic that Caroline wondered, not for the first time, how someone so sweet and kind didn't get walked over by some of the more difficult sets.

"No, Kate, I'm sorry. I was miles away. Not your fault, I've... I've not been sleeping well."

"Are you doing okay? I wanted to ask before, but I-"

"I'm fine."

"Are you sure there's nothing I can do? You've seemed a little out of sorts recently."

Panicked by her own lack of professionalism and Kate's concerned eyes, Caroline proved her absolutely right by walking out.

Caroline spent the following evening furious with herself for behaving so childishly. She'd alienated one of the few members of staff she was actually fond of, and confirmed that, yes, something had happened in Dr Elliot's home life and she didn't have it absolutely under control all the time. It was a ludicrously high standard, but it was what allowed her to function so well. She wouldn't be nearly as effective with the board of governors, or even at parent's evening if she was worried about people second-guessing her professional decisions because of matters in her personal life. She tried to keep the two worlds separate. John had rarely, if ever, attended school functions to which other teachers brought their partners (they both preferred it that way) and she would rather not be her sons' headteacher (less chance of Peter Hargreaves casually mentioning Laurence's poor performance in English during staff meetings) but, frankly, the other schools in their catchment were appalling.

Rather than get lost imagining a world in which William was forced to attend the local community college, Caroline headed upstairs to bed. As she had done every night since John left, she spent several hours tossing and turning. She hadn't lied to Kate about her lack of sleep. There were symbols of her failed marriage all around the house, but the large double bed was the hardest to not think about. Her last thought before she finally nodded off was a firm decision to apologise to Kate the next time she saw her.

Caroline was on her office's computer the following morning, reviewing the day's agenda, when Beverly knocked and entered with a steaming mug of tea.

"Here you go," she set it down next to one of the many stacks of paper on Caroline's desk. "Have you got a minute?"

"What for?"

"Kate McKenzie would like a moment if you're free."

Caroline sat up and took off her glasses. "Send her in."

Kate was hustled into the room by Beverly, who shut the door on her way out. Kate opened her mouth to speak, but Caroline cut her off.

"I'd like to apologise for yesterday," she spoke slowly and carefully, "I was dismissive and rude. There are a number of things happening in my home life, but it's not an excuse for how I behaved."

Kate nodded, apparently realising the significance of the admission. "It's fine, honestly. I came to apologise for prying. I hope you're all right."

Caroline briefly considered telling Kate about the whole situation, if only to have another adult (hopefully less judgemental than her mother) to talk to. She thought better of it, but was warmed rather than annoyed by Kate's concern.

"There's nothing to apologise for, Kate. Thank you." It was meant as a sincere thanks rather than a dismissal, but Kate gave a small smile and a quick excuse to exit the room. Caroline sipped her tea thoughtfully.