I know what you are going through. My old bunnyhad a abcess like that in the exact same place when he was 5 years old.The first vet we spoke to thought it might be best to puthimto sleep with the argument - "He is 5 years old after alland bunnies get about 5-6 years old, so we can say he has lived hislife". The vet also said that it is great risk that it will come back.
The bun was the love of my life so I insisted in a operation. He gotthe pus drained out and then he had a big open wound for quite a while,during that time it needed to be cleaned once a day and he needed totake painkillers and antibiotics.. It WAS terrible, I heard him shatterhis teeth in pain by night and all I could do was to give himpainkillers and just have him close to me.. Neither of us could sleepmuch.
But! He got well! And he lived to be almost 9 years old. I'm still kindof mad at the first vet for proposing euthanasia so lightly.. And Istill feel amazed that my bun let me clean his wound, it hurt ofcourse,but it was as if he knew it helped him.. :rose: