ourselvespronoun
Ourselves refers back to the speaker and at least one other person already meant by we, either as the object of their own action or to show that they, no one else, did it.
reflexiveused as the object of a verb or preposition when the action affects the speaker and the others in the same group, the same people who are the subject
Ourselves is used when the subject and the object of the same clause refer to the same group that includes the speaker: we blamed ourselves. It is not just another way of saying us: when the subject is a different set of people, use us (they invited us).
for emphasisused after we, or at the end of a clause, to show that the speaker and others, and no one else, did something or were affected
This emphatic use often comes right after the subject or at the end of the clause: we ourselves don't believe it; we built the shed ourselves.
Phrases
Word family
Usage
Ourselves refers back to a subject that includes the speaker, usually we, in the same clause; it is not a more polite or formal way of saying us. In they invited us, the subject they does not include the speaker, so us is the form to use.