Mark Ruffalo:The whole experience of getting close to mortality changed my perspective on work. I wasn't enjoying acting before: I felt like I wasn't in charge of my career. I wasn't doing things that made me feel good. I was really bitter, I thought I deserved more, and I wasn't grateful for all the great shit that had happened to me. If you're not grateful, then it's very easy to be an asshole. After the brain tumor happened, I realized I love acting, I've always loved it, I may never get a chance to do it again.