Hello David, when I read:
"I wish to introduce myself. My name is David. I am 73 years old, a widower as of 2 1/2 years ago. I was married (only once) for 41 years. I'm pretty much a shy loner and do not make friends easily. I don't do social media, so just joining this forum is a hard step for me."
My thoughts were, "well done you." A forum like this can be a help in many ways, there's many interesting subjects, you can dip in and out whenever you wish and you will find that you have much in common. Condolences to you on your loss. I do hope that you stay a while.
If you Google: "New Forest, England," you will see where I live.