It's hard to be a parent to a child who's never there.

Last night was a difficult night to sleep. Steamy, sticky. I was overtired and stressed by a challenging work situation. Miss Three-Going-On-Thirty decided she wanted to sleep with me, then not with me, then with me again, until Beloved lurched under his own personal thundercloud to the couch to sleep.

We all finally, gratefully, slid into something approaching restful sleep when I was suddenly jolted back to uncomfortable consciousness. Slap, slap, slap. Drip, drip, drip. Light was streaming in through the door. I moaned and looked at the clock - 12.30am. What the?

I staggered down the hall way, and bashed on the bathroom door.

"What on earth are you doing?"

"I'm having a shower, mum." I swear, I could hear her eyes roll from the other side of the door.

Greta Garbo, almost eighteen, is her own woman now. She's left school, she's got a job, she's looking forward to university, and she can come and go as she pleases. Completely obligation free, mind you, and any attempt to assert boundaries at this tricky phase (ie, the one where we don't actually have to put up with crap if we don't want to) result in accusations of emotional blackmail and hoisting "the sword of Damocles over my head". I swear she said that. Or maybe I'm trying to make myself feel better that she may be intensely irritating at times but at least she's literate.

What we don't seem to be able to come to an agreement on is what are reasonable boundaries, and how much she should be able to exert her independence at the expense of other people.

"You won't let me have a shower in the morning, so I'm having one now!" she shouted at me, each syllable waking an extra individual. Calculations of how many minutes I would have to spend settling each child, and how many minutes that would leave before I'd have to get up for work flew in a panic through my mind, as the taps poured on.

We don't allow the two big girls to have showers early in the morning. That may sound draconian, but we have seven people living in a house and one bathroom, and two parents needing to get three children ready for school and to get themselves ready for work in the morning, leisurely teenage showers are not a luxury we can afford. For those two, oh woe, the shower is off limits from 10.30pm until 8.30am. There are many, many hours within which to ablute.

I want to explain this to Greta Garbo, but unfortunately she's not here. She's never here, or when she is, I'm not. My only mode of communication is via unanswered text messages (she never takes my calls) or hastily written notes on the back of Miss Three-Going-On-Thirty's artwork from daycare. There is no chance to repair to the rhythms of a relationship of give and take - the nitty gritty necessary to making the household run must be thrashed out in the ten minutes or so our paths cross. The less we see each other, the bigger the barriers become. And it's frustrating.

At the moment, it's also impossible to take her out for a coffee and talk about things like adults. Becuause any attempt to put my case is met with the sarcasm, raised eyebrow and ever-escalating hyperbole as she demonstrates that for her, being adult means never having to sit and listen to something you might find vaguely challenging.

I love her to bits. But something's going to have to give. I look forward to writing a serene and self-congratulatory post about how I managed to completely solve the dilemma in between making school lunches and breakfast on a Wednesday morning whilst simultaneously signing readers, filling in excursion forms and approving homework.

I'm a superwoman, after all. Shower schedules shouldn't be beyond me.