elder bunny

Question
I have an elder bunny that I rescued I have had him for 8years. when I finally got him to trust me and let me bring him into my home, I had him checked out at a vet. They told me he was about  4 years old.
My question is about a month ago he was flat out, shaking out of control, took him to the vets they did Xray and found to be he has severe osteoarthritis from back of head to tail, also found a nodule on his lung. They said it could be nothing , gave him an injection for arthritis and went home he was back to almost normal in days of injection then went down hill rapidly. He was lbs at vets now looks like 5.
He stopped eating/drinking. The vets say he is in his double digits of age he probably is giving up, that what they do when they get old. Is this true?
He has been living in the house has had a great life his own bedroom nice soft bed,two litter boxes, food,hay,water,treats the whole 9 yards people say I'm crazy, but he's my little boy. Has his own radio to listen to music 24/7 central air in summer, heat in winter.

He has been loved so much and taken care of I have been force hand feeding,not working so for a week.It has been a battle.
I wont give up I got him to take pedilyte today 2tsp from dropper, 3 tsp tonight. Eating not well at all, One strip of parcley half of baby carrot last night.
I refuse to give up am I hurting him doing this should I have listened to vets that he has given up because he is my baby and I will not give up yet.
He rolled over today I thought that was a good sign, but he still can hardly walk he wabbles.
Please help scared mommy for her Thumper.

Answer
hi Beverly when you know that all rabbis are classed as adults at 5 months old you have a very very old rabbit and i,m afraid the vet is right.
just give him all the love and attention you can and he will be a very happy bunny but you must expect that he may not  recover.
Dave