I sat there, lost and cold because I was betrayed by the person I didn’t expect to hurt me.
I think the actual sentence is:
I sat there, lost and cold because I was betrayed by the person whom I didn’t expect to hurt me from.
So we see that the relative pronoun whom and the preposition from are ommited here.
How can we recognize this type of sentences? Is there any rule to omit the relative pronoun and the preposition in such a way? I know about ommiting the relative pronouns. When the relative pronoun refers to the object of the verb then it can be done. But above that one has confused me.