@Angel23,
How do you know her bosses don't know about customer and employee complaints about you? Some people don't complain to your direct supervisor, they go to the human resources and customer service department supervisors to make complaints.
Besides, why does that matter. Your boss has told you why she has distanced herself from you and stopped personal conversation. Why isn't that enough for you to respect her and act accordingly?
It sounds like the only way you will understand things is if you are fired again. You are on thin ice, Angel. They have plenty of documented incidents, performance reviews, warnings, etc., to fire you at any time. You need to get your act together. Your supervisor is trying to protect your job for you, and her job. Stop making it so hard for her to do so.