Adductors? Frozen hip? Not sure what?? Help please.

I have a client with an issue I need some input on.  I work for a chiropractor and we are both scratching our heads about a patient of his.  I have been working with chiros for the past 7 years and this is my first stumper,  The client is a female forty something 5'6 about 150 lbs.  She is a smoker but she leads a somewhat active life.  Her right leg is the issue.  As far as she knows she has never had an injury but she does feel the restriction in her thigh and groin area.  When trying to do any PNF to her hip flexors or IT Band area, the Dr and I can not get her leg to cross in the front, over to her left side.  He adductor are as tight as can be.  I do deep work on her adductors, abductors, hip flexors, along with stripping and then range of motion.  We will go from her leg being at a 90 degree to having full range of motion so I can externally rotate her knee and tuck her R foot up near her femoral artery on her L leg (butterfly position).  Afterwards she is great.  But then we jump to two days later.  After two days she is back to where we started.  We have her stretching like crazy and her son even does PNF with her everyday, especially butterfly stretches with her adductors.  The Dr. and I considered frozen hip syndrome, but the things he and I are doing would work for that and she should sustain for longer than 2 days.  Has anyone ever experienced this or heard of it?  Any ideas on what to do to alleviate the issue, or what the issue is?  What are we missing???  By the way before I get to her leg at the start of the massage I am performing deep tissue on  b/l erector spinae, ql's gluts, piriformis, TFL IT band, and I am doing TPT where needed.  Any insight is welcomed and appreciated.