Jackie, try to mainly concentrate on yourself first. I know this is so hard, but your Dad and son will also need their space. Again, try to take a few moments at a time in quiet time (perhaps to cry, as I was told we have a huge bucket of emotions that need to be let into that bucket); e.g., resentment that our love one was taken home to Heaven before we were really ready for the surreal of it all. I was also given the advice in "how badly I missed my Mom" was to first write everything you know about your Mom and save it on the computer. Perhaps you can write her what you would of spoken of if she was here. Remember it's okay to cry while doing this. We have that barrel or bucket to fill yet.
Jackie, I know how you are feeling as I went exactly through the emotions you are feeling. I'm so sorry you're experiencing this. I had a few suggestions. Just try to get through the next 5 minutes--perhaps walk a block or even down the driveway. And, another thought was pick up a "Word Search" book. You won't believe the vocabulary that vanishes from your mind; but do a few words at a time--then put it down. Don't expect too much from yourself at this time! I took care of my mother at her home until her death Valentine's Day '09 to a painful lung cancer.