Ima try to give it a shot. Bare with me...
the feelings are real, the thoughts driving the feeling may be distorted and therefore unhealthy, but still a real feeling. Eg. I'm so much better than everyone else I poop rainbows! Yes, I can feel that, but the thoughts are still distorted, and I need to remind myself that I'm still a mere mortal no matter how many times I check the toilet! Same can be applied to suicidal thoughts, and the subsequent feelings of worthlessness and hopelessness. Am I making sense?