That's strange, I'm sorry you have to go through that. Could she possibly have any mental illnesses or disorders (just throwing this out there) like early onset alzheimers (could be why she mixes up words) or even bipolar or autistic or anything? It actually could have more to do with her age than you're giving credit to.
My mom has always been strange. She would use emotional manipulation throughout my life - I remember her often crying to me (the furthest memory I have is around age 6) about things other people had, like how much bigger her friend's house was than hers (ours). I often suspected her of being bipolar, or narcissistic, and at times even sociopathic. She was very mentally abusive and even accused my dad of being inappropriate with me which never ever happened because my dad is a saint and wouldn't do that in a million years - but her twisted ways of thinking didn't stop her from accusing him of that IN FRONT OF ME at age 12.
I too feel grossed out sometimes when I talk to her. It definitely drains my energy. She never seems to actually be there for me - whenever I tell her about my problems or ask for advice she gives me very immature advice that I would expect from someone younger than me, not older than me by 30+ years.
Anyway, I just want to say you're not alone. I guess we really can't expect parents to be what we need them to be.
I've come to realize that the people who act strange or abusive were probably abused themselves and haven't learned how to manage their feelings or interact normally with others.