No sunlight in kitchen
It sounds like you have three different issues.  One is sunlight, which doesn't directly affect your problems, but could be remedied perhaps with something like this: http://sunpipe.monodraught.com/#new-sunpipes-by-monodraught (there are other brands and I've even seen DIY versions)

Next is fresh air, in your case it sounds like you're going to have to offset the building blocking your windows with fans to increase the airflow.  Maybe something as simple as a box fan in the window?  

Lastly, humidity control... If a dehumidifier isn't practical for you, there are dessicants that are sold for camping, or boating. They're often just containers of silica gel that absorb moisture and can be dried out in the sun or a stove when they are "full".  Perhaps some of those where you store your goods that are prone to getting moldy.

Hope this is helpful...