Not Waving but Drowing

What do you do when somebody close to you lies and lies and lies? They lie to you. They lie to everyone else and they lie to themselves. What do you do when this is someone you care about and who says they want your help? What do you do when they are family?
All you cut and dried, black and white people would say "kick them to the curb", "enough is enough", "it's not your problem", let 'em sink or swim".
Let me tell you, I used to try to save people. I would rush out at the slightest whimper and wade up to my ass in other people's crap. It kept me from saving myself. And I knew I could help people and save them. I know better now. I still help folks, just not as often and not as much. I often wait to be asked.
But some folks are right there drowning in YOUR pool. Sure you invited them over and they brought their towel and a couple of brewskies but then all of a sudden they are at the bottom suckin' the grate. What do you do? You jump in and get them. But then the next day they do it again! And then you hear that they did it over at whats-is-face's place. And you're thinking "What is wrong with this person? If you cant swim don't dive in, ya dope!"
But here is where it gets hard. What if they feel compelled to jump in- even though they cant swim? They just have to be near the water, they promise they wont go in this time, just need to hear the lapping and see the sunlight reflecting... then WAMMO! THEY ARE AT THE G.D. BOTTOM AGAIN!!! Maybe it's not their fault they keep going under, maybe they are retarded or crazy. Maybe medication or water wings would solve the problem. But no.
I don't know what to do any more. Because when it comes right down to it, I am getting wet just as much fishing the poor idiot out every time. But he's family.