Littleannie
You can buy portable bidets from ebay for about £8 which are a bit like a bedpan and which you can fill with warm water and sit into the toilet bowl (with the seat up), I use mine to freshen up whenever needed.
However, It is very helpful to sit in the warm water bidet and maybe have a tap trickling into the sink to enable you to wee into the water if you have cystitis or similar, it will sting/burn less.
My mum used to swear by barley water to neutralise urine acidity, she would boil it up herself (not use the Robinsons stuff). I suppose before NHS and antibiotics this was the type of remedy they had to use.