I am very sorry to hear of your loss. I have lost loved ones as well and the pain can be great. I have listed a few tips that have helped me in my time of transistion after a loved one passed. Hopefully they might ease your pain as well.
Spend lots of time with your faimly, it will not only help them, but help you as well. When we give we receive.
Try not to get bitter as some do in these instances. Things happen when they do for a reason. We may not know that reason, but someday I think you will.
While it might be difficult to go to the gym, you have to try, even if you have a far shorter or easier workout than usual. Keeping at it will help your mind set.
A good friend of mine lost his Dad as well three years ago. Each year since that time he has dedicated a fund raising Softball game in his fathers name. This has helped him keep his Dads memory alive and also do some good for the community.
Finally, try to take one day at a time. Keep your thoughts in the present moment, and try to keep busy with your daily routine as best that you can. And never think that an expresion of sorrow (crying etc.) is a weakness!
If there is anything that I can do for you don’t hesitate to PM me.