As angry and wronged as you may feel, UA is not really the culprit here. As you stated, most other airlines have higher fares, which may or may not also have penalties attached to, and may or may not be refundable. You bought the cheapest fare without regard for the associated rules, which were available for you to see. How does that make UA the culprit? It is the problem of living in a free market.

I suggest you simply try a nice letter to WHQ. They may give you some sort of refund, but that would be UA being nice, not something you are entitled to. As for trying to "dig up" an obituary, pun aside, they usually require you provide the name of the mortuary and/or a copy of the death certificate faxed to their offices. Trust me, they have heard and seen every lie in the book, and know how to guard against them. Try one, and you can kiss your money goodby for good.

It sucks, but you took a chance on a bargain fare and lost. Your flight credit is good for a year. Take it and say thank you.