Question stated above. The quality of your eggs and desirability drops off at 30, and even more so at 35. Let's say you're 27 and haven't been married yet, but you've had one or two boyfriends and know how to be in a relationship, be feminine, and generally know what values and characteristics you'd like in a future husband. You meet someone and your life goals align (marriage, children). You date until your 29th birthday, and realize you are not a match. Or worse, you meet a man at 29, and he leaves you at 30. Now you have 1 year (2 at the most) left to find a man willing to marry you, and it takes time to get to know someone.

How soon in a relationship should you cut it off if you don't have a proposal when you're over 25? Should you continue going on dates with other men WHILE you are in that relationship to make sure that you have a backup option before 30, in case your current guy decides to leave you?

I understand women should date seriously with the intention of marriage starting in high school so they have a few chances before they turn 30, but let's say, for argument's sake, this never happened, which happens to the case with a lot of college-educated women today. What's the best optimization strategy here?