/feels/ - personal experiences

My best and only real friend has several mental issues and has had many episodes with me in the past talking about how they want to die, they don't see a future for themselves, and living is just causing them pain. They asked me if someone is suffering just by being alive, has no goals or purpose and wishes they were never born why shouldn't they kill themselves? I didn't know what to say, all I could do was remind them that me and all the people who care about them love them and will be hurt. They just said time heals all wounds and we would eventually move on with our lives. All of this is sadly the truth but it hurts to hear someone you care about say this. They said they would end it soon, maybe sometime this month. I wish I could give them the drive to live but I can't. We've been through this so many times before I don't have anything more to say to convince them that life is worth living. Even the meds they take and therapist can't help them. I don't know what to do other than love my life but I hate it. I feel so helpless. I want to help and save them but at this point I don't know if they are just too far gone.