If tuning your mother out is the best way of coping with it right now then go ahead and tune her out.Talk with your friends about it.Most importantly do not believe the lies. You did not cause any of her problems and you certainly was not responsible for your father's death.Check to see if there are any ACoA or Alanon meetings in your area and ask one of your friends to go with you.
Good luck with your studies. If you continue to be brave and positive during this terrible situation you will soon be able to rise above it.