Almost completely nature.
Dropped in a b***hole of insanity, random stuff happens, expected to know what to do with all of it.
I think most of the bad things that happen are a result of a struggle against (or with?) nature anyhow. Nature forces necessity, necessity forces compromise, compromise can often mean something bad. A lot of times choices are between making someone else suffer, or suffering yourself. Either way, someone suffers, and I don't think that either is "good". The world is full of organisms who don't even know each other who are forced to kill and injure each other just to survive. It isn't even ideological, it's just some arbitrary way that things work that happens to be as close to evil as I can think of. And a lot of what we do as humans is an attempt to get as far away from that dynamic as possible, but society is modeled on it, it pervades everything. We keep the machinery hidden so that we can pretend like it's not there, but it is. Industrialized farming is one nasty compromise that we've made with nature, basically creating hell on earth for however many creatures, because if we didn't, our lives would be (not proportionally, imo) more difficult.
Society is an offshoot of nature and human behavior, human behavior is an offshoot of nature and society. It all comes back down to nature. Forgiving people becomes way easier once you can figure out how to trace what they're doing back to nature, too.
I do blame myself, and others, and society, too, but as extensions of nature. When it comes down to it, we're all fucking lost in this miasma, being forced to do and be things by nature, and everything was at least at one point a complete accident. That's how I feel at least idk. I know there are a lot of other perspectives out there, and some might be able to invalidate mine.