Search Results: my best friend gets mad because of my boyfriend

My older sister is 18 years old and a very, very sensitive person due to past childhood traumas. She’s dating a guy who’s in her graduating class and he seems like a really nice guy (#1 in the class, valedictorian, going to the same college as my sister and sensitive like her). But, the other day, she went and took my mom’s car to see him for 4 hours after my mom told her to see him for 30 minutes. So today, my aunt came over then my little sister told her everything my older sister been doing (like she was jealous). My aunt texted my older sister about everything my little sister spilled and my older sister seemed okay.

Then my little sister loves to cause trouble then start texting her as our aunt by going in on her for doing all of this with her boyfriend. My older sister completely couldn’t handle the pressure being put on her, so she completely shutdown. Like she put her earbuds in playing sad music, catching an attitude with everyone who tries to talk to her, locking herself in the bathroom, and weaving anyone trying to hug her. I got pissed off because my older sister is like my best friend and she’s going back into this shutdown mode. It usually lasts about a week before she comes back to her senses.

I told my little sister she should go ahead and tell her the truth, but my mom told me no don’t do it. I’m like it’s better to tell her the truth instead of letting her be pissed off at everyone. She should be mad at her little sister for being a jealous, vindictive asshole. But they kept saying no don’t it, just let her be the way she is.

Should I let it go or tell her the truth?