When we get angry about specific words, that's a mental defense at work trying to protect ourselves from being overwhelmed by all the feelings we really have towards our abuser. Good for you for identifying your anger. That's a sign of growth.
Tell your therapist when you feel angry at anything in the therapy room. That's an excellent opportunity to learn more about yourself, and work on building that therapeutic relationship where deep healing happens.
It's a therapist's job to keep at prolonged exposure therapy. Words which are triggering to us control us and negatively affect our lives out in the real world. They're just words. We can only extinguish that trigger by hearing and saying them over and over again. It's better to do that in the therapy room than be triggered by hearing them when you're out in public.
But if it's too overwhelming, tell your therapist.
It's also the job of the therapist to perform patient education. Informing us about the internalizing of our abuser's words is painful to hear, and takes time to come to terms with the fact that we've been unnecessarily hurting ourselves with those words for a long time. The silver lining is, once we realize those thoughts aren't us, we can leave them behind and replace them with self-affirming words.