I've been thinking about this thread; sorry for the late addition!
I have been thinking about how, culturally/in terms of society and attitudes etc, marriage is seen as more of an option for men whereas it's more of an essential for women.
So, while marriage is a choice for either sex, the alternatives are wildly different. If a man never marries then that's a perfectly fine thing in the eyes of society, whereas for women it's seen as more of a terrible predicament. So, of course, the goal becomes marriage in order to avoid that terrible predicament, consciously or not, whereas for men it's a more equal choice; marriage with a woman that he loves and makes him happy, or eternal bachelorhood which might be lonely at times, but at least he'll probably have friends, a career, etc, and he won't have to put up with a wife he doesn't like.
That's why I think it's important to keep reiterating the idea that it's okay to be a single woman, it's not some terrible fate, it is, in fact, preferable to being in a shit marriage. Women can be eternal bachelors too and have friends, a career, children if they want them, and not have to put up with a husband they don't like! Although it seems ludicrous, there is still a double standard.
I think it's also the reason why it's okay to question relationships, certainly not a bad thing. I still find there's a lot of hostility to this kind of suggestion, though. I suppose because it's not nice to think that people doubt your relationship, but if something happens that makes you look twice at something or something happens to make the relationship "rocky" that's not necessarily a bad thing IMO. If there are issues to expose then it's best to get them to the surface and either sort them out or work out that they're unsortable, sooner rather than later.