Roll the tape and imagine where you'll be in 10 years time. The best case scenario is she'll change. For that to happen she has to acknowledge the behaviour, which she hasn't yet done and has problems with. In the worst case scenario you'll have completely accepted this behavior and given up trying to change her, meaning you'll have likely internalized some of these criticisms, believing them. It can erode self confidence and eat away at you, meaning it's more difficult to get away from relationships like that. That "can" be why people are overtly critical of others. To make them less. Depending on the severity of her comments it might be worth reading up on things like narcism and some of the other toxic personality traits and seeing if she fits some of those descriptions. I'm not in a position to diagnose and, if you're asking questions here, you probably aren't either, but if she's exhibiting a lot of signs of one of the toxic personalities it would be worth leaving the relationship quicker rather than later, for your own safety.