Guilt

It’s a tough one . I am so sorry you have lost a friend . Goodbyes are so very hard to go through .

Sickness and diseases are very hard to understand . It remains a mystery to me why one person responds and another with the same cell type does not . 
Take the time you need to grieve , for me that is important and priceless as it means to me they mattered .

However you matter too and honour their memory in your life . If you would like to speak to our helpline staff they would be happy to chat this through with you as it comes up a lot .

Guilt is a strange emotion particularly when you are so not responsible for any of the events that brought about this situation. You have been through a lot yourself and deserve to  live and enjoy your life . 
Take special care ,

Court 

As I understand it "survivor guilt" is an established aspect of PTSD (I should probably say here I'm not a doctor, but I am a doctor, just a doctor of computer science). You've been through a rough time; it's not your fault that other people have too. I got my own cancer diagnosis last year, just in time for Xmas, and went under the knife on Twelfth Night. The doc said there was approximately a 15% risk to life. That's about one in six -- the same odds as Russian roulette. It's in the nature of stochastic phenomena (told you I had a PhD in computer science) that you can't do anything to determine them. Imagine rolling dice, and if you roll a six, you die (I had a pulmonary embolism a few months before my cancer diagnosis with substantially the same odds, so I got two rolls of the dice). It's absolutely not your fault if you rolled a 4 and a friend rolled a 6. The two things are entirely independent, and you can't (pace Kate Bush) do a deal with God to change your places.

So please don't feel it's in any way your fault if friends didn't make it. Old Man Death comes for us all, and the best we can do is to make sure there's nothing left unsaid to our friends before they go.

Sorry to keep banging on about my own experence, but I have found it useful to think a little about the friends of mine who have had it worse than me. It's not that I am in any way pleased that there are people worse off than me, but it helps put my own relatively lighweight problems into perspective, and helps to keep me from wallowing in useless self-pity. To this end I very much like, and have learned by heart, an A E Housman poem, which I will now inflict on you all:

As I gird on for fighting
My sword upon my thigh,
I think on old ill fortunes
Of better men than I.

Think I, the round world over,
What golden lads are low
With hurts not mine to mourn for
And shames I shall not know.

What evil luck soever
For me remains in store,
'Tis sure much finer fellows
Have fared much worse before.

So here are things to think on
That ought to make me brave,
As I strap on for fighting
My sword that will not save.

Hi Tony1960 I think it shows what a thoroughly decent human being you are! I do understand why you question your situation compared to others. When I got diagnosed, a friend of a friend was diagnosed too. She had teenage children and I don’t have any. I remember thinking how I’d gladly swap places with her, just so that she could see her kids grow up. Sadly she died. The only way to reconcile how we feel about our own situation, is to think of our friends and loved ones. They wouldn’t want us to trade places with those who are worse off. Be extra kind to yourself and live your best life. It honour’s those who haven’t been so fortunate.