If you love her I would try and help her. Get her into to see a doctor and help get it under control, you could also go to classes on mental health.. You may sorta know how she acts, but you don't know what it's doing to her until you learn about it. Leaving someone because of a mental health issue is not a good thing to do in my opinion.
if you love someone truly don't leave them. if you really love her you can't leave her. we should accept others with their flaws. that is true love.you loved her because you like something in her character na? then why you can't able to accept her negative.