I have been in your shoes very recently and if you did indeed make a mistake and talked about your room mate then maybe you could sit down with her and tell her you were wrong and you understand her anger.
We all want to be liked and respected. Most of us have an inborn trait to be kind and we do our best to help others in need. We are not dumb, we are kind to a fault sometimes.
The problem is that in our kindness and sharing we sometimes leave ourselves vulnerable to the nasty, selfish people who are only pretending to like us to satisfy their own agendas.
Take a good, hard look at this friend. Does she genuinely cherish your friendship , or is she using you due to an ulterior motive? Just my 2 cents worth.
Try not to isolate yourself to just a few but make friends with many just don't make the mistake of depending on those friends to make you happy. Your happiness comes from within and only you can control that.
This may be a friend that is not good for you. When people start screaming and yelling at us it does hurt as we are generally blind sided by the attack. Try to put it into perspective that her behavior was inappropriate and then decide if you want to mend fences.
I am glad you came here for advice and support.