Thanks, everyone. I doubt anyone IRL would buy a book of mine ? who?d take the advice of someone whose baby wakes 5 times a night? 
Speaking of which, DS is currently standing in his cot complaining at me. I went out for the evening & when I came back he?d been awake just over 1.5 hours. So now he?s on the second 1.5 hour cycle, oh joy. 
Getting mobile is irritating, isn?t it, but it?s nice to be in company.
In the last 4 days, DS has learnt to wave, pull up to standing, climb two stairs, shuffle along the floor pushing the washing basket, and is trying hard to start cruising along furniture and climbing over things. I?m not surprised that things are haywire sleepwise. We?re back on short naps too.
We never had problems with sitting up in the cot though, so take heart. :)
IC, the more stories of progress the better ? gives us all hope and strategies to try.
SAA, glad your DS is getting better. We had the same thing ? long naps at points without resettling (on Sunday I woke him after 2.5 hours at lunchtime!). There were some long sleeps at night towards the end of his cold and I hoped it might help him develop better habits. Sadly not. 
Curly, sending more unmumsnetty hugs (thanks for the explanation, IC) It?s horrible when you get mad with them, isn?t it ? I was like that with DS tonight when he wouldn?t stay still for me to get him dressed at bedtime.
I know Moxie says that it?s often when you think you really simply cannot carry on that things suddenly seem to turn a corner. I hope that?s the case for you.
In the meantime, remind yourself that it will improve - if only because she's exhausted. It's extra horrible when you're on your own, isn't it?
Kaymer, I lost all my baby weight when DS would only sleep in the sling ? but put half of it back once he started taking naps at home! 