That may or may not be a bit of an understatement...

that is one of the saddest things i've read on this site. your boyfriend is a jerk.

your bf is an asshole. and your sisters a whore

Agreed. Win.

Smallpox is more painful though

serves her right? are you kidding me? your one of those dumb people who say they deserve it over something that they don't have a say in or they don't control. I pity you. OP, I'm really sorry that that happened. in sure it's been a while by now and your over it, hopefully, but he was a douchbag. I do believe in second chances but only for the truly sorry. I hope it all worked out for you. :)

you c***

first

second

That's a dumb thing to do. It's kind of implied that she dumped him after this. Unless something happened since yesterday night and it's become normal for people to stay with their BF/GF after they cheat. @OP: your BF and sister are both cuntrags. I say you take a shit in a bucket or something and then go to their place and pour it over their faces.