Assuming her credit sucks due to being late or not paying......
Address the credit problem NOW (before you get married). Although it will not effect your credit score, there is # of reason why you should do it prior to this big commitment.
a) it will give you a chance/glimpse on how you 2 will deal with serious issues
b) you will be ready for big purchase (house etc)
c) there will be less risk/chance of your credit being effected by her ways when/if you do get an account together.
d) if she is not willing to work on it/address Debt issue or even feel obligated to do so.....that's a GREAT sign for you right there prior to marriage!!!
Remember, once you get married HER DEBT IS YOUR DEBT!!! If you don't address this issue NOW, it will/might spill onto you and next thing you know..... YOUR credit sucks.....and worse case scenario you end up with HER debt.
If she simply has NO credit, that's a totally different problem that you don't have to worry about AT ALL. Building good credit is easy (I've done it for my wife, she now has a better score than me!)
Her debt is your debt is false man, anything she had before the marriage and in her name won't magically become his debt if that's what you're inferring... If you're just trying to say that he'll have to pay for it, then that's another story, but just want to be clear that any debts she has now will never be his unless he signs something saying otherwise.
