My DD has just turned 2. When she was about 20months we started introducing the potty as she was showing 'signs' of being ready (we didn't force it & just let her sit on it when changing her, then at regular intervals). She was very good & started to ask to use the potty on occasions. We didn't ditch the nappies as felt she was still a bit hit & miss & accidents really upset her no matter how calm we were about it. About 8 weeks(ish) ago she started completely refusing to sit on the potty at all (we didn't force it as don't want her to feel upset about the potty IYKWIM). Over the last 2-3 weeks even changing her nappy (pull ups) has become a complete nightmare. Changing her nappy results in a full on tantrum/screaming/tears for about 20-30mins & the actually nappy change is accompanied by her going dead weight and lashing out. At the moment it seems to me that she would be completely happy to be left in a soaking wet nappy all day! 
The very few times we have managed to get her to sit on the potty over the last couple of weeks she hasn't done a wee at all. She is very aware of doing a poo & will tell us she has 'finished' but then won't let us change her & she won't sit on her potty to do it.
Should I just not bother with the pull ups & hope that a few days of accidents persaude her to use the potty again? Do I not even mention the potty & persist with the nappy changes? We explain to her that if she used the potty we wouldn't need to change her nappy & she usually just sobs 'no, I don't want to'! I'm at my wits end & covered in bruises from the kicking! :( Getting clothes on & off her is a complete nightmare at the moment too. I know it's probably just terrible twos but it's really wearing me down. Any suggestions welcome, just not sure what's best to do. She definately knows what wees & poos are, but has stopped saying anything about doing a wee, presumably so we don't change her nappy!