That is a tough situation to be in. Kudos to you for getting out of there! You noticed all the signs. The erratic behavior. the stumbling, the not taking no for an answer. You got yourself out of a bad spot and just in the nick of time. Time now to end all communication. You may want to help him, but hes bad news so I would do as everyone else has said and find a new group if you can. Im sorry you had to go through all of that, and I am sure you are shaken up, but you have to be selfish in situations like this and look out for yourself.