Bennett, Judith M. & Amy M. Froide eds. 1999. Singlewomen in the European Past 1250-1800. University of Pennsylvania Press, Philadelphia. ISBN 0-8122-1668-7
While, no doubt, many lesbians in history made their peace with the need to accommodate marriage and family life, when designing a character who has the freedom to refuse marriage to a man, it helps to know what social and economic options would have been possible (or even normal) within your setting. There have been several excellent collections of papers (and even more monographs) on the topic of singlewomen, but I believe this was the first significant one to appear.
I have been intended to do a summary article on options -- both social and economic -- for unmarried women, similar to the summary articles I've already done on crossdressing and on sexual activity. To my mind, it's one of the key topics in creating a historically plausible context for lesbian characters who will appeal to modern readers' sensibilities.
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