Stage 4 NSCLC Chest always heavy

I had a lobectomy of the lower left lobe in September 2007 after being diagnosed with nsclc, stage 1a in July of that year. The heaviness in my chest since the surgery never went away and now it is even worse. I had almost 2 yrs. of clean scans and then in October 2008, I was diagnosed with stage 4 nsclc. I have been on chemo since December 2008 with no success. The cancer has metasticized to the right lung and nodes in the chest. I know I should keep a positive outlook, but it is tough when I am always tired and my chest is always heavy - feels like I'm carrying around a boulder in my chest on the left side and sometimes on both sides of my chest. The only relief I get is when I go to sleep after taking morphine. Is there anyone else out there experiencing this heaviness in the chest?