They appear to be invincible, professional athletes do, with so much money, so much fame, so many people to help with everything — a first-class life, everything taken care of. And then the difficult, lonely moments hit — maybe in the middle of the night, or maybe just out of nowhere — and they struggle as many do to handle them, the tugs of life overwhelming. DeMar DeRozan, who would seemingly have it all, knows those struggles — those times of depression, anxiety, loneliness — as well as anyone and they are his demons to deal with. “It’s one of them things that no matter how indestructible we look like we are, we’re all human at the end of the day,” the 28-year-old Raptors all-star said. “We all got feelings . . . all of that. Sometimes . . . it gets the best of you, where times everything in the whole world’s on top of you.” DeRozan is unimaginably wealthy, uncommonly famous and has at his disposal a virtual army of family, friends and support staff arranged in part by the Raptors. And still . . . At home among his family, a break from the everyday grind of NBA life upon him, DeRozan found himself in one of those dark moments in the middle of the night a week ago in Los Angeles. And in a moment that belies his very private nature, he made a cryptic comment on his Twitter feed that was a glimpse into a previously hidden solitude.