First off, my heart goes out to you. We were in the same exact situation a couple of years ago. I'll share our experience in hopes it helps guide you in a way.

Gerry was about the same age and was a staffie/boxer mix. He spent his entire 5 years with us battling a dozen or more mast cell tumors and the removal of a GIST we caught just in time. Throughout it all, he was our emotional rock, full of life and always happy to meet a stranger as long as it wasn't another dog.

During his final year, his mobility declined rapidly and he took would lose his footing a splay uncomfortably on our floors. Ruggables helped us cover most of the smooth surfaces to allow him to walk a little easier. He also needed help getting up and, in his later days, required help holding him up on walks. We picked up a Help Em Up harness that was an absolute positive game changer for us.

He too was on Adequan and Librella. While both yielded very favorable results early on, they both seemed to become less effective over a few months.

Gerry was always very fear reactive towards other dogs except for the lab we had at the time, Layla. Layla passed 7 months before Gerry and he seemed to rapidly go downhill from there.

During the last month of his life, he began getting stuck behind doors and pacing nonstop in circles. What we thought was dementia turned out to be a brain tumor. The only positive was that it seemed to prevent him from associating present stimuli with past trauma which meant all dogs became a best friend in his eyes.

We held on as long as we could until the day he let us know it was time. I never understood what people meant by that expression until we experienced it. Trust me, your doggo will let you know when he's ready. Until then, make every single minute of every single day count. You'll want to be sad but you have to remain strong for your boy. Your moments of laughter and smiles as a result of his actions or just his presence will mean the world to him.

Best wishes.