Get rid ( = free oneself)
Incorrect : I am trying to get rid from her.
Correct : I am trying to get rid of her.
Note: 'rid’ can also be used as a verb and then also it takes the same preposition after it.
For example:
One day we shall be able to rid the World of this terrible disease.
Note: The past simple form of ‘rid’ is 'rid’ or ‘ridded’. Its past participle form is ‘rid’ and present participle is ‘ridding’.