I'm going to bring up dirt on my sister after she put dog shit in my boyfriend's bed
How did your sister end up at your bf's place?
My sister lives hear him and it's long distance.
Your sister is horrible for putting dangerous fecal matter there, so all of you need to sit down and sort your problems out. You are all family and you need to act like it, or it will continue being broken and your boyfriend might get sick if she keeps up these nasty acts.
She needs to know that it's her fault that he's leaving.
I'm sorry that your sister ruined your relationship. That isn't okay. She needs to know that what did wasn't acceptable and is dangerous too.