Dan, there are many factors that are not not included in your question. There is nothing stopping the United States Attorney from bringing the same or similar charges. There is no such thing as double jeopardy as it relates to state and federal offenses. It's important to speak with a lawyer who is familiar with federal procedure and the sentencing guidelines.
Mr. Piper is correct; a divorce is the way to go.
If you've contacted Legal Aid in Dayton and meet the financial threshold amounts set by that agency then it should be able to help you. You may also meet the requirements set forth by the Dayton Bar Association's "Greater Dayton Volunteer Lawyer's Program" for legal assistance.
What Happens Now? Most likely you will receive a summons to appear in court for a misdemeanor charge of petty theft. You may also receive a legal notice from Walmart requesting that you pay a civil penalty. Payment of the civil penalty will not aid you with regard to the criminal charge. For the criminal charge, I would suggest that you contact a criminal defense attorney to further discuss your options and potential defenses. Further, depending on the jurisdiction you may have the option...
In Ohio an person is able to apply for an expungement only if they are cosidered a "first time offender". That means only 1 conviction.
You are probably out of luck unless the two offenses arose from the same incident.
You must wait 1 year from being released from from probation. Then you can file an application for expungement. In the Dayton Municipal Court the filing fee is $50.
I'd have to have additional information to answer part two.