My sisters bf part 2

For those have read my post about how I absolutely hate my sisters bf here’s an update. He texted me last night saying how he really hates me so I block him on everything. This morning I tell me sister what happened and she already knows. She let him text me that and didn’t even stand up for me. I told her to tell him not to text me anymore and all she said was “how do you know he’s texting you Still”. I’m really done with her. She’s turning into an asshole just like he is and I’m not going to stick around for it.