http://Meetup.com is commonly used by people for meeting up. Perhaps if this or something like this were made easier to use and more accessible to the elderly and others with issues it could be used to bring lonely people together
yeah, it's not solved by technology alone. but you could imagine how people could sign up to a service that connects them, with additional assistance. and actually getting people there mentally + emotionally, man, idk, needs lower social stigma in general