Other than that, try every door including the rear hatch. Even if you have to climb in the back and over the seats, once you're in, running the engine and heater should help thaw out the doors and door seals.
Thanks so much for that suggestion. There was no way I was going to get in through the other four doors as they were stuck shut, even after I poured warm water on them. That always worked with my other car which is a 1986 Honda Prelude but but it does not work with the car I am driving now, which is a 1999 Honda CRV.
Thank God I was able to get the key into the back hatch maybe because the keyhole is not directly exposed to the cold air, and then I was able to pry the window open and then pry the door open. Then I got my step-stool and crawled in through the back into the front seat and started the car and let it run for about 10 minutes with the heat on full blast. I still cannot open the other doors but that's okay. I am short and pretty agile, so it is easy to crawl through, especially because all the seats are down flat except the front seats.
This afternoon when I have to go out I will crawl through the back again and be on my way. I doubt that will warm things up enough to open the front doors but I'd rather wait till they thaw on their own as rain and warmer weather is coming soon and then all this will be history.