Menu Doesn't Show Up

I am so beyond frustrated at this point.

I am using the 2015 theme. No matter what I do, the Menu will not show up on my site. I have added the menus. I have added items to my menu. Inexplicably, it simply will not appear on the page.

Oddly, even when I try different themes, the menu will not appear.

I am new to this, and I am by no means technologically minded. But I have spent hours trying to come up with an answer to this to no avail.

Please, please help.

My site is here.