Even though Kate Middleton is currently battling cancer, she is still trying to get out there and attend events. So much so, she was able to be at the Trooping the Colour on June 15, though she was “exhausted afterward,” a source said. “It was a long day, and it took a lot out of her. That’s why she wrote that June post,” the insider noted, referring to her lengthy Instagram post in which she detailed her health battle. “She absolutely has bad days, and that’s something she wouldn’t have shared in the past. Kate’s not the only person battling cancer, and she realizes that being truthful about …