I'm sure you realize that it's easy to be depressed if you have a chronic illness.

https://www.sciencedaily.com/releases/2014/08/140827203635.htm

From the article: 

An analysis of data from more than 21,000 patients attending cancer clinics in Scotland, UK, published inThe Lancet Psychiatry, found that major depression is substantially more common in cancer patients than in the general population. Major depression was most common in patients with lung cancer (13%) and lowest in those with genitourinary cancer (6%). Moreover, nearly three quarters (73%) of depressed cancer patients were not receiving treatment.

I find it terrible that doctor's don't do more to heal us from our emotional as well as physical ailments.  I have discussed the emotional toll that kidney disease takes on you and your family : Depression in Kidney Failure

If you are concerned that you might be feeling depressed, please talk to your doctor about it!