This is what I did..

when i started I would take them with me and make a joke out of the sound of my wee hitting the water.. Gross yes but hey its your kid

for poops I would empty the nappy into the toilet and we would giggle about the plopping sound it made

then I would talk about how much fun it would be if they could make those noises too.. then we would sing silly little toilet songs and some pretty gross ones.. Bit IMO it made for a very relaxing time.

I found DD so hard to get out of nappies. you aren't a failure she is just taking her time to get it Maybe pop her back in nappies for a couple of weeks to give you both a break and then in about a weeks time start talking about it again but not excessively. like when you are cooking dinner, washing up or whatever.. just bring up the whole no nappy thing and how she is a big girl now yada yada..

then maybe one morning say how would you like to try getting rid of those yucky smelly nappies today? Lets try the toilet this morning and see how you go.. Maybe pop a nappy back on and every 15-20 mins take the nappy off and take her to the toilet

Are you using a potty or the toilet? Personally my boys hated the potty but DD didn't like the toilet and wasn't that fussed on a potty so we put a potty next tot he toilet as well as a toddler toilet seat so she could choose which one she wanted..

Good Luck.. I hope she gets is soon for you..