When will I feel better?

I am trying really hard to overcome these feelings but thry just wont go away, I have a sick feeling in the pit of my stomach and it just will not go, I feel moderatley better of an evening but I put that down to having got another day over with, I really dont want to just feel like I am getting through my life and not enjoying it but that is how I do feel, I think things like it must be so much easier to be older cos then you have the right to feel llike this, I am only 38 and should be looking forward to the rest of my life not dreading it. I have survived cancer and i dont want to waste my time now that doesnt seem right, what am I going to do?