I Feel Guilty

I feel guilty that I don't like to help my friends out sometimes. Not that I never want to help them. For things that have an answer I do. Like giving advice. But a lot of times, my friends come to me for things I can't help them with. Like how I have one friend who experiences a lot of pain from health issues and vents to me about hating going to the hospital. And my mother friend who got mugged at gunpoint and is still traumatized and tells me he's scary and sad. I can't help any of them but they want me to say something. I never know what to do in those situations but if I don't say anything then I'm a terrible friend.