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Sorry to hear about your problem.
Houses are continuously being built tighter and tighter these days and this reduces the amount of air flow that can flow back and forth, from the outside to the inside. Older houses could "breathe" much easier and this allowed the moisture to escape. Unfortunately, alot of heating and cooling escaped as well. Now that the houses are tighter, the heating and cooling is contained inside the house much better, but so is the moisture in the air. This is when condensation begins to appear.
Condensation and frost on the windows is a sign that the humidity is too high in your house. The humidity or water vapor in the air is caused by humans respiration and perspiration, showering, bathing, cooking, gas appliances, washer and dryer, plumbing leaks, exposed dirt crawlspaces, indoor pools/ spas, fishtanks, greenhouses with plants, etc. All of these add up and dump water vapor into the air, but there are ways to control it and it is good to start with the larger sources.
Using ventilation all the time will help; always use exhaust fans when showering and cooking and verify that they are exhausted directly to the outdoors. A dehumidifier can help pull moisture out of the air, as well. If you currently use a humidification system, I would stop using it. Dryer vent needs to exhaust to the outdoors. Let me know if you have a dirt crawlspace because that can dump large amounts of water vapor into the air and I can tell you how to reduce it.
The humidity should be between 30 and 60 percent in a residence. A small, inexpensive and easy-to-use instrument called a hygrometer (sometimes referred to as a humidity sensor or relative humidity indicator) can measure the humidity level in your house and confirm whether the house has too much or too little humidity. Once you know for sure, you can decide whether any action is required and, if so, what action.
If you need further help or clarification on this answer, please do not hesitate to reply to this post.
Thanks for asking your question at Just Answer.
Best of Luck, Brian
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