From personal experience (not with a spouce but with a soulmate that had cancer) we put so much of our self into the care....& time we spend taking care of them & trying to figure out the best care.....this becomes our whole life's identity & purpose.
When they are gone, we not only don't have them but everything we have spent our time on is then gone too. So not only is there the loss of your loved one but also the life style you have been living & there is a totally lost feeling that overwhelms us.
There is really NOTHING except time & getting used to the change in life situation & accepting the grief & tears as they come.
Sometimes immersing one's self in a career helps distract but going through the feelings of grief is important because it is the only way we really can process our new reality even though we KNOW before it happens that it is happening. I still have tears & a hole in my heart after losing my soulmate 1 1/2 years ago. Life goes on.....but it goes on differently & adapting is all part of the grieving & healing process.....that doesn't mean the loss isn't still felt it just means getting more comfortable in the life yiyr loss has left you