This might be an overreaction (Hypervigilance) and do you believe he may have a formal thought disorder (i.e., was speaking in a strange manner, and was generally suspicious of you) Did he ever physically abuse you?
All I can suggest is to be yourself and ignore people like him. I am on meds too and I know how it is like to be scorned. It's not a "sign of weakness" but rather biological system suffering from physical damage (change in the anatomy of brain, change in its chemicals, metabolism, infection or injury etc.)