EX:

-          He said nothing more, because he did not want to add insult to injury.

-       I took the damaged suitcase back to the supermarket. The assistant refused to give me a refund. To add insult to injury, she accused me of damaging the suitcase myself.

-       The guest of honor arrived at the charity concert and was told to queue up like everyone else. Then, to add insult to injury, the doorman would not let him in because he did not have a ticket when he finally reached the front of the queue.

To queue up: to join a queue (a line of people, cars, etc. waiting for something or to do something)