That bipolar i also recognize with the coke addict, some times in a high mood and than depressed. Is a sickness. And acting like nothing is wrong and everybody is the bad guy. One of my best friends had also that biploar and high/down problems, months/years everything went great, good job, nice girlfriend, and in a down period realy depressed and than he would get back on his feet. He commited suicide 1,5 year ago. I lived 3 months with him in his house on the Dutch Antilles and helped him out cause he also helped many times the 25 years we knew eachother and he was one of my best friends. Everything went fine so i traveled further, and 1 year later he killed himself. I talked a lot of him about suicide and i can tell you that cost a lot of energy, altough we also had great moments when he get back up.
When they called me that he commited suicide i only had 1 question, did he go alone... he could have killed his ex also in a depressive state and there where times that i was on the point to inform his ex to be carefull when he had plans to go to Holland.
This are situations you must take seriously. Don't try to help someone alone, ask a shrink to help him, and support/inform you how to handle the situation. Cause a lot of times they look for an excuse and a sort of 'approvel' to commit suicide cause the world is bad and no reason to live, feeling a loser (what he wasn't). Shrinks know better how to deal with that.
I can tell you it was for me also a rollercoaster dealing with that friend. But i am glad i could help him out and get him back on his feet, though it went wrong anyway 1 year later. Letting behind an ex with 2 young boys. I didn't know he was down again, kept that a secret and pepared his suiicide. I am glad i visited him, he called when i was in Thailand, one week later i was in the Antilles cause i am in the circumstances that i can live where i want and travel the world since 5 years. I am glad i helped him, his parents said that did him a lot of good and gave them alo more rest that somebody looked after him. But it wasn't enough...
I would only help close friends and would do it again. But helping somebody that is not so close to me, i will avoid them. It will suck all energy out of you and you must have a strong mind to deal with that situation. That drug addict, i took my loss and shut that door. I can understand if you get fooled by someone that you don't care what happens to him, revenge is sweet
Good luck to someone that want to help him, else he will be a homeless addict or dead within a few months/years. And having bad habbits, i have seen with the drug addict what that does to your brain, you will never meet a more manipulitive person than an bipolar addict.
just putting my experiences here for if somebody has to deal with a situation like that.