You’ve done a lot for your sister. You gave her shelter when she needed it. You’ve taken care of her for longer than you probably should have given the fact that she was using drugs around your child and bringing shady people into your home. She might have bipolar disorder and that is unfortunate but she also is an adult who is irresponsibly engaging in drug use around your child. That type of activity endangers not only your child but also you and your husband. Given these circumstances, giving her an ultimatum was the correct choice. I know it was difficult because you’d hate to see your sister suffer but you have a family that you need to care for and protect. She was endangering your family and so she had to go.
I am not sure I understand your question regarding extreme pill addiction and how that might affect her chemical imbalance. If you are asking whether drug use worsens bipolar disorder the answer is yes, usually it does. It’s not clear whether the drug use led to the bipolar disorder or vice versa but undoubtedly drug use negatively impacts bipolar disorder symptoms.
It was very thoughtful of you to take in your sister when she needed help but it was the correct choice to make to ask her to leave when she began using illegal drugs in your home, around your child. Hopefully in the future she can get the help she needs and then it may be appropriate to allow her back into your home. You can and should support her in her attempts to get help even if they seem half-hearted. Addiction is a very difficult problem to overcome and it usually takes addicts many attempts to finally quit. With your love and support she might someday be able to beat her addiction. Thanks for writing.