Mentally not stable. Which isn't her.

I don't how to say, But by mom behave unusual sometime I mean she say whatever...Sometime she talk nicely to someone and on the next moment she start fighting with them accuse them and abuse sometime. (She is almost 45years old) She say whatever unlogically and without thinking..Always when start fighting..Use high peach (Scream and Shout) out side. Some time looks like something got into her. I think she lost her Reasoning and Logical power. She do all the household chores almost nicely. She always watch preaches of saint's on TV or outside. But I don't think she understand what they says. I mean when we talk to her... Sometime she misinterpreted it and think completely wrong way. Or even when we try to make her understand, she didn't understand and take it wrongly and fight...accuse, abuse, start old talks, some time talk fantasy thing...Which never happen. Accuse person of something which they didn't did. Tell thing's mine which isn't her.