Carol,
The alone feeling you feel is very common among those of us who have had our only child die, and we live alone.
I live alone, have no relatives living close to me, and like you, I feel lonely a great deal of the time.
My son was killed in a accident, but the lonelyness is still here. My son also lived out of state. But, I talked to him almost daily. There are times, even after 8 years, when the phone rings at a odd hour, my first thought it is him. Then, the pain is back, because I know he won't be calling again.
I would like to tell you the loneliness goes away. But, like everything else in this life.. I have good days, and I have bad days with the lonliness and I imagine a part of me will always feel lonely.
Love and Hugs
Peggy