We had a Jack Russell terrier that acted the same way after my husband got sick. Before my hubby was sick, he could play with the dog, they went for long walks, and things were fine. The dog had loads of energy, but we could handle him.
After my hubby developed heart failure and had trouble getting from the bed to the chair, all that changed. I had my hands full working fulltime and taking care of my hubby and my elderly mom who also lives with me.
When my hubby would have to be in the hospital or we would be out of the house for any length of tim, the dog would go NUTS doing all the things you mentioned. We knew we couldn't let him destroy the house and we couldn't keep him in the back yard. We contacted the Jack Russell terrier rescue group and our JTR ended up going to the Navy to be a drug detection dog on the ships.
We knew he was just upset that my hubby was sick, but we just couldn't handle him and he needed a JOB!
We felt horrible that we had to give him up, but we had no choice.
It sounds like you don't either.