How long do people commonly survive with diabetes survive when it is at the stage of retinopathy & gangrene?

My mother is 73 and has arterial leg ulcers which are at high risk. The doctors have also stopped eye laser treatment to halt eyesight loss as it has not worked. I hope it's not too morbid a question, but I am wondering about life expectancy, what care is likely to be required, and what actually causes death for people with diabetes because gangrenous limbs can be amputated...

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).