Hey girlie,
I had some serious irritation and thrush issues down there a few months ago and completely feel for you! Its horrible.
I got told by my doctor that femfresh and all of the vaginal cleansers are all just marketing hype and should be avoided, as well as normal soap and shower gel. Water should do the trick, but I know for me I always feel a bit paranoid about just washing with water. My doctor gave me some Aqueous cream, and that has been wonderful, its not scented but I still feel that it cleans, as it lathers up a little if you dilute it. Best of all its really cheap and you can get it in boots

I think my doctor gave me a specific one for washing though, so you might need to find that one.
Good luck
xx