When suicide is the only option

Here’s my story. One year back I was the happiest man alive. I had a good job. I had just got promoted. I was the senior most in my office. My marriage was fixed. Then this eye problem cropped up. The doctors diagnosed me with a rare incurable genetical disease. In just a year I’m now almost blind. My muscles are so affected that I’m wheelchair bound. I have lost my job. My fiancee left me. I have lost all feelings in my body I can’t feel hot or cold. Now the doctors say my kidneys are also failing. I’m in constant pain. I’m just a burden for my parents. Every day feels like hell. I wish I was never born. I know that death is just round the corner. But I can’t bear to face it. I feel suicide is the only option for me. Just need the courage to end it all. Please suggest a way to painless suicide. Please help me.