None of this is to suggest that age-gap relationships can't or don't work, of course. This research simply focused on the distinct issues that often come up in relationships where one partner is significantly older than the other.
The linked article above provides a lay summery of the study. Full study available here.
Partnership remained the anticipated long-term destination, while singlehood was treated as a temporary period of preparation and personal growth.
Women who remained happily and voluntarily single in their forties and fifties described having their contentment questioned or dismissed because others assumed that a relationship was necessary for happiness.
Single positivity therefore appeared to broaden the identities available to younger single women without displacing the underlying couple norm; women could celebrate being single, but were still expected to settle down eventually.