Rob Thomas, 50, is a Grammy-winning singer-songwriter, a solo artist and lead singer of Matchbox Twenty, which is planning an upcoming tour. He spoke with Marc Myers. 

When I look back at the low points in my childhood, I’m amazed I survived and emerged where I am now.

My mom, Mamie, married at age 14 to escape her abusive mother, Mattie. She had her first child at 16, divorced, remarried, had me at 21, and divorced again when I was 2 in the mid-1970s. 

We were all but doomed to a life of poverty. But to her credit, my mother did manage to give us a better life. 

After my mother’s divorce, we had to move into Mattie’s two-story house outside Lake City, S.C. It was attached to her general store. My mother, my sister, Missy, and I lived downstairs. Mattie sold liquor illegally stored in a secret space under the stairs.