Usually yes. If someones repeatedly telling the same story then obviously it had a big impact on them negatively or positively, its a child or elder and I'll let them continue. If someone does it to boast then no, I'll cut them off.
How do you deal with someone you know isn't giving you both sides of the story but they're portraying themselves as the victim?
Yes but I keep in mind that it could be a mistake, not their normal behaviour or response, keep my thoughts to myself and give them a second chance. If its reoccurring I'm just done
Edit: yes some people do try to convince themselves but it's apparent