Is it wise to change my supervisor in the late stages of my PhD? I have been doing my PhD for 3 years, and my supervisor has been a real pain. This has made my life like a hell. His behavious includes yelling, bullying, and demeaning me. He has no regards for me and he does not keep the privacy about my work. Since, other people in our group are all from his country, I am the only one with whom he speaks/yells in English, so almost everybody at school is aware of the situation. His bad manners are not limited to this, it is much worse, but I don't want to write about him, rather I want to write about my problem.

I wanted to change my supervisor in earlier stages of my PhD, but the school suggested only one option whose research area was quite different from mine (We work on similar problems but completely different approaches). Also, because my stipend was sponsored by his grant, I had to apply for another scholarship. In the end, I decided to keep working with the same person (ignoring this bad behaviour) and avoid a new unknown situation. 

Later in my PhD, I came to know other supervisors at school and started working with them. Though, I kept working with other professors, and I kept my main supervisor notified about what I am doing. He was also happy, because he could see that I am much more productive. However, his behaviour remained the same. Every time that I talk to him, he kills my motivation and self-confidence.

Now that I have finished 3 years, the scholarship has ran out and the supervisor failed to provide me with any financial support. Unlike him, other professors has been really supportive and provided me with some financial support. I still have a thesis to write and I really cannot tolerate his behaviour. I was wondering if changing my supervisor at this stage is a wise decision. What are the drawbacks of this decision?
There is no harm to change supervisor if he is not supportive nor encouraging nor friendly. Because in most of the cases, he is the only person whose recommendation you need to get your next position. So first of all, think how much of your present work can be added to your final thesis if you change a supervisor. If you can add more than 50-60% of your present work, then it would be a great decision to work with another good supervisor who is really supportive and interested to work with you. It is not a good idea to change a supervisor, if you plan to do everything from scratch again as it is already passed 3 years.