u/K1L0BYTES

Back in highschool (2009-2013) I read a book about a person who had the ability to absorb pain/illness from others via skin to skin contact. The MC could then turn it into a spring-like crystal and expelled it from a hole in their side. I remember at the end, they find out that all those crystals were alive and had been shipped off to a wasteland.

EDIT: Solved

The book is The Healer by Michael Blumlein.