There are four occasions I can put my finger on where I just wanted to walk away.
The first two were formal rush during my sophomore and junior years. Both years, we had the Tyrant Bitch Queen of Rush running things (which I guess you need during rush, but still... argh!) I felt like I was going above and beyond while some other sisters weren't pulling their weight, and it was infuriating. (During my senior year, I was a rho chi. Also stressful, but a different type of stress.)
During my junior year, I went through a bad breakup and really felt that some of my sisters weren't there for me.
Then, I came back as an alum to help out with rush, and the chapter president was very rude to me. I swore at that time that I would never have anything to do with my chapter or AEPhi again.
It was only recently (actually, a result of my having found Greekchat!
) that I came to realize that it was silly to write off 50,000+ sisters because of something one sister did years ago, and I have slowly started doing things on the alum level and reconnecting with my chapter.