I think that it is quite sad that he died as he did, and lay dead and undiscovered for so long. I'm not sure that that means he was an SOB. More accurate to say that he was profoundly troubled.

He was an alcoholic, had been diagnosed with schizophrenia and treated for it with shock therapy, and, grew up in an abusive family situation. At a certain point, he became reclusive. Bolinas, where he died, is, or was at that time, a place for reclusive people of various types.

This thread has tended toward disparagement, so I should point out that there has been a relatively recent reawakening of literary interest in his works. He may not have been a great writer, but his work is interesting. He has a unique point of view, a direct and terse style, and is often quite funny.

It may have been Lawrence Ferlinghetti who said that Brautigan understood trout better than than he understood people. That is quite a shortcoming, for a writer, but nobodies perfect.