I think that is really messed up. Marrying someone is one of the most important decisions you can make in your life, especially if you're planning to stick with them until you die.
I think you need to spend at least a hundred hours (preferably, even more) together with a potential mate, before deciding whether you want to spend the rest of your life with them. A hundred hours together could be a 60 or 70 dinner dates, and weekends spent together, which you could do in less than 6 months.
Everyone puts on a show in the first couple of dates, and it takes a little while to get to know who a person better / for who they really are.