I know how you feel. It wasn't that long ago that I was doing a dozen or more walks a day in very cold temperatures. She will learn.
Urinary tract infections (UTIs) can cause frequent urination. Your vet can examine the urine for bacteria and blood cells to rule this out. The good news is most of these can be treated and resolved with the appropriate antibiotic. Changes in toilet habits are worth having checked by your vet.
I know this will sound frustrating, but you may need to go back to square one on the house training. Do not let her have any unsupervised time. This includes when you are sleeping. Please consider crating her at night. Dogs typically will not soil their den areas, so she should not eliminate in the crate. You might still want to give her a walk mid-way through your sleep, just in case, for a few nights. Increase the amount of time each night by 30 minutes or so until she is dry throughout the night. Using old towels or an old blanket will make clean up easier than a nice crate bed.
When you are home keep her attached at the hip--literally. Use the umbilical leash method. Put a clip on your beltloop and attach the loop of her leash to your belt. The other end stays on her collar. You will monitor her constantly this way and she will not be able to have an accident. When it isn't safe for you to have her at your side, put her in the crate. Take her outside at least every 2 hours during the day when she isn't in her crate. Yes, at her age, she should be able to hold it longer. As the dry days add up, increase the time between walks. If she gets used to going when she wishes, she may need to relearn some bladder control. The adult dog we got had been kept outside and urinated when-ever she wanted. We had to slowly train her to have stronger bladder control. You should be able to get her back on track in just a few weeks. I know it is frustrating. Others have given advice about scheduling her feedings and this is very important. You could even remove her water a couple of hours before bedtime if she is healthy.
One final thing. How are you cleaning her accidents? You need to use an enzymatic pet cleaner like Simple Solution or Nature's Miracle. If she is still smelling her urine, it will attract her and let her think this is the place to go. Good luck. Give us updates!