To answer the thread question, yes. I'm in the top 2% of intellects, which has segregated me from most of society because, like toddlers, the average person doesn't understand me, the world, or themselves. It's incredibly isolating. I was r*ped before I even got my first period by my textbook narcissistic mother's summer fling when I was 12. She consciously orchestrated my being alone with adult men dozens of times, including leaving that man she didn't know to babysit me (he's now a prominent member of my university in my small little town when he went to COLUMBIA). She tried to sell me off to men that she believed to be Saudi princes on Facebook at 17, attempted to get me to adopt a stranger's crack baby at 16, tried to get me to be a surrogate for her husband's sister at 15 the "natural" way (thankfully it didn't happen, but not through the adults' lack of trying), and forced me to spend 18 hours in a move across the country not with her, the dogs, and my sister, but with two grown men in a moving truck, who, luckily, were not perverts. My family refuses to validate that I was intentionally given the cruelest, most sadistic treatment from my mother while my sister, a self-centered, soulless brat, was the golden child. I've attracted nothing but my mother's ilk with my good heart, and all it's gotten me further abuse: physical, mental, verbal, sexual. After enduring all of that with my husband for almost five years, we're finished because he assaults me when he has schizoaffective manic episodes. Ergo, I'm ready to shuffle off the mortal coil.
I believe anyone's reason for CTB is "enough." Plenty of people have endured far worse than I have. It's about not wanting to continue a life from which you've not gleaned any happiness that isn't as transient as the people who come in and out of it.