history: My best friend left me alone at the bar while I was drunk. I expected her to call a cab and make sure I got home safely, but instead I was left alone with a random stranger. Hey you will not believe what Sara did last night. She left me at the bar all alone with a random stranger even though she knew I was intoxicated. Dang that Sara!  Did you tell her how unhappy you were with her? Yes_comma_ I have known her for years so I forgave her but I really expected a lot more from her. You know what I mean? 
current: Yeah I understand.  Maybe you should pay her back somehow.
next: Hmm, yeah any suggestions on what I could do? I don't want to do anything too mean or that could put her in any danger though of course. 