I am just glad you HAVE and option. I can see both sides and I guess I would go with what you can deal with right now as far as what is going to keep all of you sane while helping difficult child.
It sounds like OR would just send you into a spiral and possibly make the rest of the family worse... this place may have the same options for difficult child in the long run?
Even though you can't "stay" with her, would you truly get to stay with her in OR. I am sure you would not get to participate in her treatment?
Visitation will be good once you get into the swing of things and you can see that she is responding to treatment.
It is not going to be easy no matter what you choose. Lets face it, she needs some serious help and this is not something that any parent wants to do. You are amazing and you are strong.
Just make sure whichever place you choose truly understands what she needs and what every one is expecting. Sometimes things get muddled up in the stress of it all. And make 100% sure that you insurance is OK with it!!! Triple check with the place that they have pre-authorization...
She will get through this and so will you. 
