Ethically, I cannot tell you to lie to your probation officer.
If you are concerned that she may violate you, you may wish to contact an attorney who specializes in federal criminal law in the court in which you are on probation. Sometimes, an initial consultation is free or at a minimal cost. You can discuss the specific facts of your case, evaluate your options and decide how to proceed.
If she already has information regarding your bank statements and rent checks, she probably already knows. If you are not forthcoming to her, she may make it MORE difficult on you if she has to expend more time and energy to prove something that you could have just told her about and admitted to doing.
Oh, in response to your question, what I meant was that the PO could note the information in your file and decide not to violate you, but instead decide to close the file.
If you are honest about the "petty" violation, she may treat it as "petty" and not violate you--especially since you have had NO other violations since you were on probation. You could explain that it was a transitional time because of the pending divorce and that you were going to tell her, but with everything else on your mind, you simply forgot.
You are REALLY taking a chance by trying to ride out the storm and hope that she doesn't find out before your probation is over. It probably isn't your best choice.
Again, if you are concerned about a possible violation, you should speak to an attorney who practices in your judge's court. The attorney may advise you as to your best option. However, P.O's have access to LOTS of information and can contact anyone. You may want to just be honest. If you are violated, let an attorney advocate your position that your probation should just be terminated and your file closed.