I think the older ladies who are gay have had to hide their sexuality over the years. I work with a lovely woman who married young, had 5 children, then met the love of her life when she was in her early 30s. The fall out for the family was immense. Her ex husband doesn't speak to her, nor do her older two children.
That being said, had she left her husband for another man, the fall out would probably have been similar.
She always knew she preferred women, but she also says she wanted children, hence the early marriage. So quite a bit of deceit going on, which may explain her husband's reaction.
Gay women now can still marry (each other) and have children using donor sperm, so no need for the pretence of a heterosexual marriage.