It really depends. In some cases, ending a person's life is a more merciful act than trying to keep them alive while they are suffering. My grandmother went into the hospital to have gallstone removal, and somehow the surgery got botched, and she became severely infected with MRSA to the point where she could not recover from it. My other grandmother doesn't have her wits about her anymore. She's had several strokes during her life and her dementia gets worse and worse. I don't think that a person's life should be ended without their express permission though - that's not really suicide anyway.

I do not believe in assisting suicide to a young person who is depressed, because situations in life can change regardless if hope is present or not. We all die regardless of temporarily extended our lives, but I don't think it's moral to encourage a person to end an entire life, over some temporarily discouraging things that they are going through.