Jelly Legs

Not long after being tapered off multiple meds (over 25 years) my friend's legs pretty much turn to jelly and she has been falling a lot.  It's difficult to tell what is really going on since she had 2 foot surgeries and hasn't done a lot of walking in 2 years.  But the jelly legs and many more falls have happened during the tapering and after.  Could this be a result of the long-term abuse of benzos?