If you two entered into contracts and have joint debts, you need to understand that your divorce is between you and your spouse.
You may reach an agreement with her about who will be responsible for which debts, but your agreements are between you and her. If she agrees, as part of the divorce to be solely responsible for ABC debt and then defaults, if both of you signed the original loan agreement, the creditor will be free to chase either of you. It would be up to you to get her to honor the agreement. It does not become the creditor's problem.
If she entered into a contract after you separated, in many states that would be her separate debt. Moreover, if she was the only person who signed the contract and incurred the loan obligation, the creditor cannot, by the magic of family law, make you liable. Whether a judge would rule the debt as part of the "marital estate" is not something that I would venture to make a guess on.
Most of the time, however, judges will not second guess what the parties decide on their marital property/debt division agreements unless something really seems really strange. As noted, creditors are not a party to your divorce. They can only chase after whoever originally entered into the agreement. Ergo, even if under FL law, some debt she incurred post separation was considered marital and a judge ruled that you also were liable, the creditor cannot directly chase you, if you did not originally sign on. It would be up to her to chase you via contempt of court motions and orders, etc. The creditor can only pursue the person who signed the loan contract and incurred the obligation.
Some exceptions may exist under the "doctrine of necessities", especially with regard to medical expenses. But, if we are just talking about garden variety consumer debt or auto loans, the above statements should generally be applicable.