Thank you so much all for the replies. The sense of withdrawing and focussing on me and the labour is definitely what it is. I'm so large and uncomfortable now and I have HG so going out much isn't really an option. I miss my friends :( But DH took off yesterday and today to spend with me and keep me company which has been lovely. He only has to work tomorrow and then Thursday is a bank holiday here. We talked it through as well and we don't think it's the bipolar. I think I'm also freaking out a bit at the idea of having a baby, it's really going to happen at last after so long.
I have decided just to take each hour, literally, as it comes and not think about the after the birth bit! Not having any experience of labour, I view it a bit like a root canal, something unpleasant that I will get through but will be worth it in the end - and the reward is much better than relief from tooth pain!
iwill that sounds lovely though, baking cakes with DD2. A nice activity to not think about the impending arrival.
everton cocooning is such a good expression. It must be a relief to be able to focus on yourself for a bit. I have been ignoring pretty much everything and everyone aside from DH and doctors. Right now it's pouring with rain outside and I'm under the duvet on the sofa with a bar of fruit and nut from Lidl which is strangely enough the only chocolate I can eat!
Ladies who manage to look after their kids and be so active and social right up to the birth I am in awe of. I know the kid thing is necessary but still, it is such a huge amount to do when you feel like a walrus.
seasalt the emotional thing totally. I'm a bit of a wreck and very needy with DH at the moment. Who fortunately is a total star. And I cuddle my dog a lot which he doesn't seem to mind :)
I see my psychiatrist and obstetrician on Friday so will discuss it then - and get my induction date if necessary! Period type cramps here have been on and off all day and quite strong sometimes. I am trying not to get my hopes up too much but you never know. When I stood up earlier the pressure down was insane and felt like the baby was going to arrive there and then 
Hope all the ladies who were having delivery symptoms are ok.