Be brave. If you want to rehome him so that his quality of life improves then you are a very responsible, selfless person.

If you feel at all uneasy about his prospective new owners don't be afraid to pull back. Have you considered getting a dog walker to give him the extra exercise?

My heart goes out to you. Keep us in the loop

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Some days you're the dog: some days you're the lampost

When I feel blue, I start breathing again