What to do is to consult a local criminal attorney - many offer free consultations. DO NOT further discuss the facts of this matter on this or any other public forum, it can be used against you. You can locate a criminal attorney on AVVO under the tab 'Find a Lawyer" Do it now
This is not intended to be legal advise or as legal representation. I am a California personal injury attorney . Be aware that every state has its own statute of limitations; and statutes & case laws that govern the handling of these matters.
Your probation officer will be aware of your second arrest. The probation officer may wait to see how the domestic abuse charge turns out or may wait until the last week of your probation before revoking you. An attorney in Lafayette can assist you if a revocation hearing is scheduled. The system is going to assume you have a serious substance abuse problem and will expect you to get a handle on it before giving you a break.
This response does not creat an attorney client relationship. In all cases, I recommend you seek a paid consultation with an attorney with expertise in this area.