It's going to be hard on you and worse on her if you stay together and you can't respect her beliefs and behaviors. Best outcome is to have a confrontation and get her some help, second best is for her to reject you and your help directly enough for you to get out. Worst is to silently allow her to hurt herself and blame yourself about it.
Also, you should decide in advance what you'll put up with, and set some lines you won't cross. It's very easy for this to gradually get worse and worse and you'll feel trapped by previous acceptance.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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