Kevin, I'm relieved to hear that you are being supported in your workplace. Since you had the night off, I hope you were able to at least rest some. Even lying down and closing our eyes helps. I used to use something a lot and now and then I still do, and that is the sounds of nature. My favorite is the sound of rain falling. There is also crickets, airplanes, fans, water trickling down...a huge variety of very soothing sounds. Well, what is soothing for one may not be for another but there are many to choose from. It may help you to fall asleep. It couldn't hurt! They are sold in drug stores, WalMart...most places. And, very inexpensive.
I know the deafening roar of the silence that you're experiencing in your home right now. It may also help to keep the TV on but on a station that's very light in content as in DIY or Home and Gardens....no movies. Keep trying as many things as you can think of and eventually, something will enable you to at least lay your head down and maybe even relax for a short time. It's little by little, everything we try. Nothing will happen overnight.
Also, gardening. Which I'm sure you have little interest in right now but maybe just measuring a spot for a future garden or project that you've been wanting to start. Write it down and put in on your frig. In fact, write everything down you're doing or would like to do and post little reminders so you will see them often.
Try to start a journal. Writing all of your feelings down. It was yet another life saver for me as I couldn't concentrate on anything for any amount of significant time, but I 'did' have strong feelings as my emotions were like a yo-yo....so I wrote all of my confusion, fear, uncertainty....everything I was feeling and after writing it I would feel like a huge weight was lifted.
You could write to your wife. Letting her know how you feel and how much you miss her. It will help.
The ones who offered to do things for you, call them and let them know you 'do' need help. Maybe they could pick up groceries for you and run similar errands. A home cooked meal would be welcomed.
Be sure to drink plenty of water/Gatorade or Powerade...just keep plenty of fluids going in. SO very important. Water adds oxygen to our blood stream immediately and perks us up. Gives us energy. And, grief severely zaps our energy level. Try something different every day. Take care of yourself the best you can. And, know I am here for you, day or night.
Sending you a big hug, love and understanding,
Terry