From what you are describing I am assuming you mean her cornea is turning white and her sclera is turning red. The cornea can become 'cloudy' for a number of reasons including corneal scaring, corneal infection, corneal inflammation, corneal deposits, and corneal edema secondary to glaucoma. If it is not the cornea that has turned cloudy then it could be her lens which could mean she has developed a cataract. Did this happen suddenly or has it been a gradual change? If it is a sudden change then I would be concerned she could have glaucoma, especially since her sclera is also red. She really should be examined as soon as possible by a veterinarian to evaluate her eye and do the appropriate diagnostics to determine the exact cause (stain her eye to look for a scratch or ulcer, measure her pressure for glaucoma). If she does have glaucoma she needs to be treated immediately as it can cause blindness if left untreated. Below are some websites that might be helpful.
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