I think most partnership connections are achieved via word of mouth and face to face communication. I've posted partner ads on several different sites and the only replies I got were from people who didn't seem to have read my ad! Once a guy from Italy wrote me about a partnership, and I live in California and never said I would relocate. Another time I said that I was looking for an amateur to dance in Novice-level competitions, and one guy who replied did not want to compete (and was a pro besides) and the other was a pro living 100's of miles away -- turns out he was looking for someone to do Pro/Am with. I was like "what part of 'looking for an Amateur partner'" was not clear in my ad?
I think some people do get lucky through online ads, but I'm not one of them!
The "wait wait" time can be soul-crushing. My best advice is to not give up and also not just wait. Actively look in your area for a dance partner. Tell everyone you know that you are looking. Take group classes to try to meet partnerness dancers. If you meet someone nice who isn't perfect, but you think you'd like to try working with them, then ask them for a trial partnership.
Sometimes people can't find partners because they are needlessly picky. Sure, for example if you've got the drive and talent to make a national semi-final and have already had some success and need to find "the RIGHT" partner, then you need to be a lot more selective. But if you're trying to find your first partner, or are on a lower level and are doing this for fun and personal fulfillment, then you can think about widening your criteria so as to increase your chances of meeting someone who you can partner with.
Good luck!