Right, first of all I should probably clarify that I'm a fairly new subscriber, so I don't know a whole lot about the guy and I don't plan on stalking cuz you know.. that's just creepy.
From what I gathered so far, there's been a lot of drama in this dude's life, which he dealt with in a certain way and I guess people think he's a psycho because of that, which is ridiculous. Each person deals with pain in a different way, you can't judge someone based on his reaction to things.
I understand that he was married to someone who cheated on him and got pregnant with another man's baby which lead to a divorce and her being a dick and still collecting money off him due to not getting a prenuptial contract. While she was having a so-called mental break down in which she threatened to kill herself and frame him, he decided to film her in order to have evidence if she did attempt anything. He then uploaded the video online for a short period of time and then decided to take it down, but people had already downloaded it and is still online to this day. Viewers keep saying that filming her wasn't an appropriate thing to do, and keep blaming him for her meltdown but in my opinion he just did what anyone should do in that situation which is make sure they have evidence of what was happening in case anything went wrong.
Onision was also friends with multiple famous Youtubers such as Shane Dawson, Swiftkaratechop and Cyr, but eventually decided to end those friendships for whatever reasons. People judge him on that aswell, saying he can't maintain proper relationships with people and keep asking exactly what happened between him and the other Youtubers, which is not a very nice thing to do. Surely at the end of any friendship people get hurt, one way or another, but when you have thousands of people needing explanations it can really take a toll on you.

Undeniably he has an odd sense of humor, some people like it, some don't. Sometimes he acts like a nutcase, which encourages people to call him a psycho. Personally I find him very entertaining and quite like OnisionSpeaks which is a channel in which he talks about his life and shares his thoughts. The main reason why I feel people keep calling him insane is that he is very open about his life and experiences he had, and is very graphic as to what happened in specific situations. People tend to not understand why he did/does certain things, which can lead a more immature audience to make fun of what they don't understand, as people do.
What I really like about Onision is that he takes full advantage of all the bad things that happened to him and doesn't really let them bring him down. He entertains people with all these crazy stories, and maybe teaches them a thing or two about what it's like to be surrounded by shitty people. He makes the most of the situations he finds himself in, therefore I declare him a genius.