i'm sorry that you are going through all of this, i think that you are doing all you know how to do, but unfortunately, your daughters decisiona are hers to own. it maynot be the bf's fault that she is feeling the way she is, it maybe that she was just not ready to stop.
i'm a recovering addict and i know that depression goes with the territory. glad that she is safe in the hospital and hope that from there she can make a decision to get sober and stay sober, but she'll have to want to. if you like, you can continue to try to help her and spend more money or you can allow her the chance to help herself.
don't mean any harm by saying this but sometimes it helps more for the love ones to step back and allow them to suffer the consequences of their own actions. she may have to hit her bottom and that bottom may not be what you expect it to be. keeping you and yours in my prayers, i pray that your daughter finds her way soon.