Found it! I just located my source for the fact that women don’t have a chiyuv to get married! The reason I know this is because I asked Rav Leff about it years ago. I just remembered that the shiur (at which I asked him this question) was recorded and is on his website. If anyone is interested, you can go to Rav Zev Leff’s website, go to the Homepage, click on “Special Shiurim”, scroll down until you get to “Shidduchim -don’t despair”. The shiurim go in order of years and this one was given in 5770 (it doesn’t say the year, but the one before it says 5669 and the one after it says 5770).
If you fastforward to 30/31 minutes, you can hear me asking him this question and him answering.
By the way, it’s a good shiur for any of the “older singles” present to listen to in any case.