The “world breaks everyone and afterward many are strong at the broken places.” It’s a line from Hemingway’s “A Farewell to Arms’’ from which Mary Collins, a professor at Central Connecticut State University, and Donald Collins, a recent Emerson grad, take the title for their important and affecting new memoir. “At the Broken Places: A Mother and Trans Son Pick Up the Pieces’’ (Beacon) traces Donald’s transition from female to male over the course of high school and college and the deep strain that transition put on the relationship between mother and son. The book alternates between the two voices, Donald detailing his surgeries and hormone therapy and the joy and relief he found along the way. Mary writes of her sense of loss, of alienation from her child, and feeling excised from her son’s experience. The book is frank, informative, and makes an argument not necessarily for radical acceptance but the simple act of sitting down and having a conversation.