“I want nothing more than to be a loner,” Emily Kempf sings early on Flower of Devotion, the new album by Chicago trio Dehd. It’s a startling admission coming from a songwriter who, just a year ago on Dehd’s critically acclaimed Water, wrote eloquently about the joys and pains — more than anything, the necessity — of love, compassion, and companionship. But then, “admission” isn’t really the right word here, given the stridency of Kempf’s tone. “Loner” is a declaration.