How many females, if happily married, or serious, would include at least one pic of their spouse on fb?

I wouldn't use it to measure the quality of someone else's marriage, personally. Most married women probably have a picture of themselves with their spouse on Facebook. Those that don't may be unhappy, sure, or maybe they're just private or don't get on social media much. Those that do may be happily married, or they made be putting up a facade, like many unhappy people do on Facebook and other social media sites.