Morning all,
Thanks for the advice and support, was very weird putting only one young lady to bed last night. Feeling much better now that I now Nigella isn't going through hell, I hate seeing anything suffer.
Onwards and upwards, not sure what to do, just going to see how Fanny gets on, just want to see how she is for the next 4 weeks maybe check she hasn't got anything before we think about getting more hens, don't want new hens being infected as well.
I would love to rescue battery hens but maybe I am a bit too emotional...I'm not usually an emotional wreck, (very level headed and bubbly, personally I blame hormones!)

Decided last night that with the patio doors leading out into the garden, couldn't bear to be in the kitchen without hearing the wonderful sound of clucking when an egg is laid. Fanny is a right old clucker! I think maybe the sensible option would be like you said to source a couple of chickens from someone locally, to go and have a good look round, Butts Farm in Cirencester is literally a couple of minutes drive away, all the animals are so well looked after so think I may do a couple of visits there over the next 4 weeks and just research even more. If we get another two and they live happily with Fanny then maybe later we get some battery hens, would like a few years of death free incidents for a bit, it's been a right old month!
I can cope with red mite and louse and the odd problem, I know my hens inside out so immediately know if there is anything wrong and it's a challenge but with them pegging it it's draining and not enjoyable. Not giving up just going to enjoy Fanny for a few weeks then will decide what to do.
One question, do chickens get lonely?! ....now I have gone bonkers!

11 It's just that guinea pigs live in two's! (don't laugh!)