Urgent eye sight surgery

Hello, my name is Claire. I have a beautiful dog by the name of Milo. He is an 11 year old Shih Tzu. He is a wonderful, loving playful boy. He recently had medication for his arthritis ( I cannot say for sure that this is the cause). However within a month became diabetic. Over the weekend he suddenly lost his eyesight. I had this checked yesterday and advised its severe cateracts and surgery is possible. I have been quoted 5 thousand by willows. Milo is insured and has been since he was a puppy, but the insurance company have stated that they will no longer cover him for any diabetes related illnesses. We have to date spent thousands to get his insulin under control ( as he was insulin resistant) and have maxed out our credit cards. His monthly medication and food costs alone are costing £250 a month. I am absolutely devastated for him as he is a shell of himself. Exercise is also crucial for keeping his glucose levels down and this is now something he is struggling and reluctant to do. We have a short window to find the funds for an operation which has a high success rate to regain his eyesight if we act quickly. I know it is a big ask and I have never asked for anything before, but any support even if it is £1 would really support us in funding this operation. I will be happy to provide any proof of quotes and post his journey so you know this is a legitimate cause xxx