I need some advice please :(

I need some advice. I'm currently dealing with a very difficult buyer and I have to admit that this buyer is the most challenging buyer I've had to deal with in over 6 years. Tell me how you'd respond to this: first message..... "Dear coolshirts2cheap, I am unable to keep the clothes. I have bipolar mania. And I had a very bad episode. I had to see a state phsychologist, and he brought up so much bad stuff that I get these episodes where I spend money I don't have. I don't even have a job. I am sorry" after I responded that I would not be issuing a refund, that our policies are clearly marked on each listing so that there is no confusion I got this message....#2 "Dear coolshirts2cheap, I will be sending package If I have to get a doctors note from the physchologist. And send it to ebay I will. You see I am a serious buyer and cannot help my mental state at times. And if I have to go any further then I will write to ebay and say you have dicriminated with someone who has a disability. I have a very good standing with ebay and I will leave feedback and let everyone who is on and with ebay see how you have discriminated against me. So if you would like to go thru this than we can." I then explained to her that because she had this "illness" that it didn't make her exempt for the rules and policies of ebay and the seller. her response #3... "When people go thru these epsiodes sometimes you don't remember what you bought. I have spent thousands of dollars on ebay. And if you can't show the least bit of compassion then I will take this to the reso;lution dept on ebay. You look at how many items I bought injust a short time and tell me there isn't a problem. I am not giving you any B.S. I hate this condition and I can't help it. And if you can't show one person like myself then I feel sorry for you. But all in all I am still sending it back and if I don 't get my refund then we will have to deal with. Why don't you read up on this condition and it will also tell you that you get verry very happy and very angry, and write now I am EXTREMELY ANGRY. I just can't control my emotions." finally I told her that I would give her a refund of her purchase price, being that I already shipped her item, I will not be out of my shipping cost. her finial response was #4... "I wish I was always in control of my actions but I'm not it has even brought me to the point of trying to commit sucide. If you think I am making this up you can call my physiarst. I know it is not fair to sellers which makes me feel even worse and embarassed because I feel like some sort of freak. But the people who understood I always took care of them later on. If you look at all the feedback from the buyers they always had positive things to say in dealing with me. I am sorry for this situation I'm sorry for who I am And sometimes I wish to God I wasn't me. Like I said I am very very sorry. " I really don't plan on responding to this email, I have to say that I'm a little freaked out by this, tell me, how would you handle this?