If you request a LOA can they terminate you?

I have not been feeling well and told my boss the prior week that I was going to have a nervous breakdown. He comes in the next day and asks me all kinds of questions, calls me to his office Monday and coaches me for not getting a note done since april 19th, I was aware of the note Monday May25th firt time I heard of it. I ask to take a "Holiday Day" on Wednesday, come back Thursday and there is a investigation going on. They question me to all kinds of things and say I have favorites. They have a paper that has my electronic name on it that I pushed this girl through for a job offer and put in answere for the interview. They asked me for a statement, I said yes. I was leaving for lunch, brought the statement home, realized that they were wanting to fire me. I was trying to clear my head as to how this happened when teh phone rang and the HR man told me to put in there how I didn't select her, or try to push her through. I told him that I was remembering some stuff. I hung up and realized that they wanted me gone at this point, I started to have a breakdown called my dr for appointment. Called HR back to request a LOA, had to leave a message and told hi that I would give him my statement. My boss tried to call from a different number than ususal and left a message that he wants to meet the next day at 8am to go over results. I emailed him early the next day stating that I could not meet him and I was certain that Joe wuld've told him and I would give him my statement. I was not and still not in a good place, several people are aware of this as I would break down (and never before would I break down and start crying) I was yelling at my son and husband, unlike me. He send me a certified letter stating that he seperated me from the company based on the outcome of the investiagtion? They don't even have my statement that I wanted to give. Did they just not want to pay for me. After he coached me he sent a email to all store manager that he wants this specific thing done because it was a 5 month note? Did they all get coached. This is a six figure job I had, for 13 and half years.