Wow, I never expected so much support... thank you.

Thanks for your questions - you're all right, I haven't been very clear.
Without using any terms then, I'll explain what happens and maybe you could clarify what it is I'm doing?
My dream can start any time of the night but rarely in the last couple of hours before I get up.
When the dream starts I normally get out of bed. There's a moment when I stop to assess whether I'm 'dreaming' or the situation's real. I do reality checks and confirm that I'm dreaming and that I'm not really in a swimming pool or having to carry heavy furniture etc. This normally wakes my husband up and we've tried relaxation techniques to help me get back to 'sleep' but recently I've started telling him that I'm not dreaming, that I'm awake and just going to the bathroom. I don't 'choose' to do this - like I don't choose to be in a dream. I can't stop the dream but I can fully engage in it - acting out what ever it is that's going on. (This is what concerns me as sometimes I've 'carried' my daughter back to her room and even tried to put her back into her cot, even though I can see she's already there.)
Then there's a point of 'realisation' when I wake up and the dream stops.

A couple of notes that might help:
There have been two occasions where I've stopped dreaming altogether which were pregnancy and the Atkins diet but my doctor doesn't think they're related.

I really don't want to embrace this - I just want to stop dreaming and sleep well. I'm exhausted.

Thanks for your help everyone.

Pip.