I was precipitated into early retirement through a generous voluntary redundancy scheme that had a deadline , not what I wanted to do but what was in my best interests.
Within 6 weeks of retiring I was back at university studying for an MA in archaeology, a serious interest I had had for years and had always planned to do when I retired. Since then it has been constant activity, archaeology,10 years of caring for four different sets of relatives, major renovation of our house in France, 10 years as a volunteer with Age Concern.
Sometime I really must sit down and plan my life in retirement.
I do think many men do find it more difficult. DH officially retired from employment and immediately became self employed. He only takes on work he wants. Initially he worked about half time, but all from home, no commuting but as years have gone by he has gradually wound it down. He is 70 now and just does the odd day or so every month, most of it office based at home. It has given him time to develop other interests and activities, social and leisure.