without knowing the full dream, to dream of eels is to be avoiding a situation or responsibility in reality. snakes [and by extent being bitten] are a representation of fears you're hiding from or avoiding. so there could be a situation, or people she's worrying about and want to avoid so badly it's effecting her dreams.
while i doubt she's been cursed, she does seem under pressure and in need of some help. a build up of negative energy can be just as bad as a hex, she should have a cleansing bath as well as having her space cleanse. if she refuses, at the very least convince her to have a relaxing bath with lavender sea salt to calm down. you can do the cleansing yourself if you wish, and be sure to give her a protection charm to keep the negative vibes away. however, you shouldn't force someone to do something they don't want to [especially if you believe in the Rede] so if she really don't want to do the cleansing, you unfortunately have to respect her wishes. if you don't believe in the Rede or you feel it's right, then go for it, but think before you do.