James doesn't like sleeping, eating or having sex. Basically anything that might be pleasurable to him he finds disgusting and avoids it. He was already self destructing before he got to the town. This is even built into the mechanics for the different endings like not healing yourself right away when you're damaged. It's also reflected in various entities spawned by Silent Hill but most blatantly in Maria both in appearance and the fact that she was hardwired to try and kill herself which would torment James even more.