Yeah, I'd take it into consideration. I'd consider it along with everything about the person, and their past, though. For example, if they were in massive credit card debt because they paid for their mother's heart transplant, that would be pretty forgivable! But if they went into massive debt because they couldn't control themselves, then that'd be another thing.
But honestly, if the person was decent but simply unable to control him/herself, then I'd still have a hard time accepting the situation. There would have to be some preconditions, such as allowing me total control of the finances - right down to calling the credit reporting agencies and putting a password on his/her account that only *I* know, so that no new credit lines would be extended without my involvement.
Sorry to be so unromantic, but I do believe spending can be an addition just like gambling or drugs. I wouldn't marry even a recovering gambling addict without some similar preconditions.