It's not recommended, but I went through the same thing 6+ months one year, then a very picky summer where she would not strike the prey to another 5 months of refusing I broke and fed live.
She eats like there is no tomorrow now, but it's extremely inconvenient for me as we won't keep live rats here and then there are the other issues that go with live feeding that aren't all that great. So far we have not had problems but I'm counting on something not going perfectly at some point.
I tried it once to see if it would "jump start" her. It did, but I can't get her to take F/T'd any longer.
I agree that once they start refusing it becomes a habit then it is very difficult to get them going.
Get yourself a backup boa constrictor LOL!
Mine will eat anything it can.
Good luck!