Petra, you don't know me so I consider your personal comment about me to be inappropriate. It's really not what my life or your life is or has been, but what OP is feeling. She sounds from her email to be not just fed up, but actually depressed by the isolation, boredom and lack of human contact, to the extent where her only social life is through the internet. I admit that I couldn't live like that, I would go mad, but I appreciate that others could do so and welcome solitude. I really don't want to personalise this.
However, if I knew that my husband were as unhappy as OP sounds, I wouldn't just polish my car, I would want to help the person I loved by going out somewhere other than the supermarket or at least facilitating their life by driving them to places. There is no suggestion that he is unwell, or that he has anything else to do. Perhaps he could teach her to drive, if he can't be bothered to drive her anywhere himself.
But yes, where a loved husband or wife is suffering like this, wouldn't you want to be kind to them and make their life better? As I have said, 68 is not old these days, at all. Is this to be OP's life for the next 20 years, confined to a husband who shows little care, only virtual friends, the tedium only relieved by the occasional trip to Aldi. There is much more to life than this, at any age.