Mystery lung disease has my girlfriend on strong vent. Is there hope?

About 3 weeks ago my girlfriend Amber was having breathing problems and admitted herself to the hospital in traverse City Michigan. Things quickly took a turn for the worse and she was scared and said she felt like she was drowning. Day after day she fought as the nasial oxygen tube turned to a full face mask. Her O2 levels were dropping still and the talk of a ventilator came into play. We tried to avoid that of course but ran out of options. Ten days passed and she was scared and tired of not being able to breathe. So the doctors and us decided to have the vent put in. Within 24 hours she was in critical condition and being transferred to Henry Ford hospital in Detroit. We have been here for 9 days and she's on 16 PEEP level. Her blood gas has been dropping her oxygen has been in the 90s but when the RN tries to reposition her the levels crash. Now the doctors are telling me that she's not going to live without life support 24_7. They are suggesting us to pull the plug and let her go. It feels to soon for a decision like that. I'm terrified of loosing her. There has to be a way to help her.