I've had many occasions over the years to eat alone in a restaurant. Business trips, grabbing a meal during shopping, or just because I happen to be hungry and alone at the same time. If I don't have anything to read I usually play the people watching game. That's takes away any loneliness that might be attached to the excursion.
It's engaging looking over the room and speculating on what's happening in the various relationships gathered around the tables or booths. Families, couples, friends, business meetings - they are usually all there to watch and enjoy.
In the "couple" category there is almost always at least one couple who can be seen sitting at their table in total silence except for maybe a "pass the salt please." How sad that is. Married for many years, I say to myself. Nothing left to say; they've said it all.
How sad it is to see communication dry up between people instead of grow richer and deeper as time passes. While a comfortable silence can be a blessing, not having anything in common anymore is not. I can't imagine loneliness any greater than that.
Do you have a relationship that needs a fresh infusion of warmth and communication? Here's your clue: could that be you sitting at that table together but in silence? Try to turn things around. You have something new to say; something new to share. Ask questions. That's the best way to get the other person to open up with you. If you don't, even if you are sharing your dinner table with another person, you are the one eating alone.