What happened to these cookies?

ATL, you added shortening, which actually increased the fat in your recipe. Shortening is 100% fat, butter is between 80-84% fat, as mandated by the FDA for Grade A butter and above. That fix seemed to work for you, but I still think the problem is that the butter acts as both a fat and a liquid in the OP's cookies, since it was melted. More flour is generally needed to compensate for this.

I think the problem is definitely the fat as I said above. I used to chill my dough overnight and my cookies still melted within one minute.

Looks to me to be a problem with the fat and the dough probably wasn't chilled long enough. I find there is a lot of spread in cookies with melted butter-- the recipe has to be just right, the dough chilled, and the oven at the proper temperature.
Did your friend start these cookies in a high temperature oven? Like 375 instead of 350? I've found lowering the temp mid bake to be helpful for some cookies.

I had a similar problem with all my cookies and wrote in here about it. Happened after a move from east to west coast. Oven was fine, I chilled my dough, I used a national brand butter as well as flour so it was not a regional variation etc. I never had a problem before and always used butter. One suggestion i got was to add shortening. VERY reluctantly, instead of a stick of butter, I subbed two tbsp. shortening and the rest butter. Problem solved. Still don't know the "why" but this hasn't affected the taste.

Almost looks like the cookie dough did not get a proper chill before baking. That, and it almost looks like there's too much butter. The photos remind me of what happens when you do not properly chill a Christine Tosi cookie recipe.

Did the recipe call for melted butter? Usually butter should be just soft and creamed with the sugar for cookies. Melted butter will cause spreading like this.

Yikes! Too much sugar is usually the culprit when cookies spread too much, but these look like there is something else seriously wrong. I suspect that the flour amount is way off.

The pic makes it seem as though there was really something off with the recipe. Though cooling the cookie dough can help prevent spreading, even a room temperature dough should not spread like this.

Additionally, I would defer your friend to this lovely link by David Lebovitz.

http://www.davidlebovitz.com/2006/12/why-do-cookies-spread/

Ooooh dear, ahah.

Seems to be like there was too much fat in the recipe.