Advice needed for leaving academia
I plan to leave academia for good now. But I don't want to leave to
  live yet the same patterns in industry


You may find industry to be just as bad or even worse. People with power can be very nasty. 


  Now, I am at a third lab to finish a thesis project for my degree. I
  thought that this lab would not be connected but recently they had
  been forging new relationships with close collaborators of previous
  supervisor. Things were going well at first in the sense there weren't
  any referential or odd remarks. Recently, however, I'm not so sure I
  can trust them either.


Due to traumatic past experiences, you have developed a "paranoia". It is highly unlikely that your previous supervisor (who seems to be a big shot, with multiple "close collaborators" and a large enough lab that he can treat his lab members disrespectfully and continue to have enough members to sustain his research) has the time or desire to go out of his way to badmouth a former undergrad to a group that is distant enough away that the connection is only through his close collaborators. He might even want you to succeed in this new lab, so that you are content/happy there and less likely to bother him again (asking him for letters of references, making complaints to his university administration for abuse/racism/academic-misconduct/etc.).

However, I appreciate that you will not be able to easily trust anyone anymore. You are vague though, about what happened that made you not so sure you can trust this new lab, so I'm limited in how much I can help you there. But what makes you think you will be able to unconditionally trust people in industry? You may consider also exploring this stack exchange: https://workplace.stackexchange.com/. You may find stories even worse than the one you've described here. Finally, part of your lack of trust for people, is in fact healthy, because as you get older you'll learn that you can't trust many people in this world.


  Has anyone successfully dealt with people like previous supervisor and
  gotten away from them? Any advice is greatly appreciated.


In the comments, I've given my email address and you can perhaps tell me which field you're working in so that I can see if I can help. Sometimes it's just a matter of finding the right lab, distant enough away from the previous one. Luckily this happened during your undergraduate years. While it will be impossible for you to fully appreciate this, you are in the very very early stages of your career (considering you did a masters and two undergrads, I'm guessing you are 1-2 decades behind my colleagues and I, so still very young). This means that the stakes are very low, and there is still a chance for you to have an upward rise in your career, which will help you to forget about all the nasty things that happened to you during your undergrad years. Trust me on this. When you get to my age your troubles as an undergrad become almost irrelevant.