Not true. You can file bankruptcy after the divorce and identify all of your creditors upon the bankruptcy application. Discuss this matter with your bankruptcy atty. Most creditors will tell you that the provisions in a divorce decree will not have any affect upon their collection of a jointly held debt.
Whether you are eligile to file a Chapter 7 bankruptcy depends on a complete analysis of your financial picture. If your friend isn't fully aware of your circumstances or isn't an experienced bankruptcy attorney, s/he isn't qualified to advise you about this matter.
In most situations, it is easier to qualify to file Chapter 7 after a divorce is completed, but many times I advise people who do qualify to file together before their divorce is final to save themselves a few bucks on the legal fee & court costs.
I would be suspicious of the motive of this friend who is giving you this kind of advice. You need to be cautious about trusting people with information about your personal business, unless you want it to be spread all over town!
Hope this perspective helps!
As others have said, your marital status does not directly affect your ability to file bankruptcy. If it is an amicable divorce, I usually encourage my clients to file before filing their divorce so that the creditors cannot impose complete liability for a joint debt on just one spouse following the discharge in bankruptcy.