I spent 20yr building network of top docs. now they are starting to retire. what do i do? healthy but 65.

Income drop: I am not sure what your occupation is. In medicine, there are referral chains related to age. For instance a group of internists of a certain age refer to general surgeons of the same age. When these internists retire, the surgeon finds that his caseload and income drops. And he may have to retire. You have to assess your goals, income and future prospects. Perhaps a career change?