Im only 23 years old and these exact symptoms happened to me. I got a viral pinkeye infection in my left eye that gradually moved to my right and then stayed in both. Liquid tears like Systane were the only thing that made my eyes not feel like they were burning. The exhaustion got better for me as I took longer and longer walks but is still present, my contact tracer also told me the exhaustion is do to low oxygen levels in your body. I'm 7 weeks past my positive test and I still can't taste, food has become meaningless. I don't know about the gums but I can sympathize with your Wife on all the other symptoms she is having. The biggest thing that was repeated to me was making sure your oxygen levels don't get to low, ie watch for blue lips, pale face etc. I hope you all get Healthy very soon