Kacey Musgraves continues to show her love for her estranged husband, Ruston Kelly, amid their divorce. On Friday, the «Slow Burn» singer posted a black-and-white photo of her ex, writing a sweet note to wish him a happy 32nd birthday.«Hope you know how lucky the world is to have you in it, @rustonkelly,» she wrote, adding, «Happy Birthday! I’m in your corner.» In the pic, Kelly's back is turned and he is looking out a window.The musicians tied the knot in Tennessee in October 2017.