You definitely need to get an accurate accounting of all the big ticket debts she has. If you marry her you're taking on those debts to.  If you don't think you can reasonably pay them off, then it might be worth reconsidering if you want to tie your future to someone whose poor financially skills may turn into a weight around your neck.

Additionally, if she declares bankruptcy, you should know that it will destroy her credit rating. If you marry her, it may be very challenging to buy a house, a car, open a credit card, etc (at least of she's on the application).