I taught my son to blow his nose by first letting him pick out his own box of tissues. Then when he needed to blow, I would close off one nostril at a time and hold his mouth closed by pushing GENTLY up on the underside of his chin. With a little encouragement, he finally was able to clear his nose somewhat.
As for tushie wiping, get her some flushable wipes, like the Kandoo kind. They are scented with kid friendly smells, and they are moist and flushable. When your daughter is done wiping with them, have her let you check her and praise her alot if she "gets it all!"
If she has a confidence problem, she will need encouragement for every little thing. She may even need a sticker chart or something for her just TRYING to wipe.
GOOD LUCK!!! :-)