Is she manic-depressive/bipolar? Or mildly schizophrenic? Whatever her disorder it does not make a relationship impossible if you BOTH want to continue with it. The main thing needed is to find out what the disorder is & learn everything that you can about it so that you can identify when it is the disorder speaking & know not to take it personally.
But even so it will not be easy for either of you & you will need a strong sense of your own self worth not to be hurt by the things she says. And a great deal of patience & internal calmness to ride the waves.
And also to recognise that she also is making a tremendous effort to monitor her own behaviour, even though she will not suceed all of the time & that the effort will generally be impossible to see from the outside.
But like I said, a relationship like this is very difficult & a huge commitment from both of you. You both have to be willing to make that commitment yourselves & to allow the other to make their own choice for themself (her included) & to respect that choice. It sounds like you both care about each other very much & I don't envy you your situation at all. But, as you will have seen, there is much support for you here, whatever choices you may make.
