My son just turned 8 in July and he still wets at night, my daughter is 4 and still wets at night. Their pediatrician said not to worry about either till about 6-7, then we could try other methods (he advocates the Bedwetting Alarm, not medication). We had our first dry night with my son last night. Whoo hoo! Some kids just take longer for their bladder to develop the right muscles, and some are very heavy sleepers. (both my kids are heavy sleepers.)
If you are both losing sleep over this, and doing the laundry every day, go back to pull-ups if you can afford them. For some kids, this is a motivator in and of itself. They don't want anyone to know they are still in "diapers". My son is at the age now where a sleep over is possible and he doesn't want to be embarrassed about it.
You need to do what works best for you and your daughter. Sometimes it is by trial and error! Good luck.