I really have no words to express how sorry I am that you're in this situation. It's grossly unfair and will make for a difficult grieving period, as if grief isn't complex enough. One thing I would say is you seem like a really good person. That is not a trivial thing. Some of that goodness will have come from the things you learned about life during your relationship with your beautiful wife. The world needs good people now more than ever in our history. I am also not above doing the manipulative act of asking what advice your wife would give you, if it would provide enough food for thought for you to keep going. Please take one day at a time. Draw on your support networks and seek the support from professionals who are trained to help. I can't imagine what you're going through and am cautious at replying as I don't want to say the wrong thing. I feel in you're case better to risk saying the wrong thing as to say nothing at all. 
Please take the best care of yourself and know you're in my prayers. I hope you find meaning soon.

Thank you for your reply. You had no wrong words. My small support network has gone. I'm currently off work but find controlling emotions difficult. Usually I'm the strong one supporting others. She was a staff nurse of 22 years and the medical profession have treated her appallingly. The pain and loss gets greater every day. Can't find any local support because of covid. So using these forums to express my feelings especially the very hard times at night.

I even ordered a pendant during the night for hair,ashes or both. Hoping that may help a little.

I say do anything that helps you get through each day, as long as this won't put your present or your future well being in jeopardy.  I think we search for answers knowing that they don't really exist. It's different for everyone as we're all unique. I think some of the elements are universal, and well documented in the literature on grief, but ultimately we all have our own path through this dark wood. How we tred this path will be as a result of our past, our relationships, and will ultimately provide us with the wisdom and knowledge to move forward. For you I think a moment by moment approach may be beneficial, and self care is an essential part of that. Don't put too much pressure on yourself to resolve how you feel. If you have those thoughts that life is not worth living see them as just that, thoughts, and allow them space to exist and dissolve. Thoughts are very persuasive at times but your instinct to survive and honour the memory of your beautiful wife is stronger. Take it day to day and be exceptionally kind to yourself. You're not on a timer. This takes as long as it takes, but the feeling of excruciating loss will ease its grip over time, and you will move forward. I really hope you find the strength, even on the worse days. 

I say do anything that helps you get through each day, as long as this won't put your present or your future well being in jeopardy.  I think we search for answers knowing that they don't really exist. It's different for everyone as we're all unique. I think some of the elements are universal, and well documented in the literature on grief, but ultimately we all have our own path through this dark wood. How we tred this path will be as a result of our past, our relationships, and will ultimately provide us with the wisdom and knowledge to move forward. For you I think a moment by moment approach may be beneficial, and self care is an essential part of that. Don't put too much pressure on yourself to resolve how you feel. If you have those thoughts that life is not worth living see them as just that, thoughts, and allow them space to exist and dissolve. Thoughts are very persuasive at times but your instinct to survive and honour the memory of your beautiful wife is stronger. Take it day to day and be exceptionally kind to yourself. You're not on a timer. This takes as long as it takes, but the feeling of excruciating loss will ease its grip over time, and you will move forward. I really hope you find the strength, even on the worse days.