My boyfriend and I got into a tit for tat. He put his hands on me. I called the cops. No one pressed charges. The state picked up the charge. His sentencing is this mon. He was already on probation but for a dui. What do you think will happen? This is in Indiana by the way

What did the PO say when he called the PO as soon as he was charged with the new crime ? As you well know it is most likely a much more serious probation violation not to report the new charge as soon as it happened.

But on the current charge, sorry if it was serious enough to call the police and he put his hands on you, that is a crime, you are not required to "press charges" in fact under most state laws in the US, the police officer is required to charge someone if they go on a domestic call and see evidence of the crime.

So I would say for some reason it sounds like he did not report this to the PO, so tell us more about that before we can follow up better

My boyfriend and I got into a tit for tat. He put his hands on me. I called the cops. No one pressed charges. The state picked up the charge. His sentencing is this mon. He was already on probation but for a dui. What do you think will happen? This is in Indiana by the way

If he is convicted at his sentencing then yes, he will have violated his probation. What will happen is he will have a VOP hearing and the judge may decide to revoke his dui probation and give him some time in jail after he finishes whatever time is imposed on him with his new conviction.

If he is convicted at his sentencing then yes, he will have violated his probation. What will happen is he will have a VOP hearing and the judge may decide to revoke his dui probation and give him some time in jail after he finishes whatever time is imposed on him with his new conviction.

Incorrect, actually merely getting arrested is the offense and in most areas you may have the hearing before you ever go to trial on the new charge.
If they did not very quickly report the new arrest to the PO, they could have serious trouble at that point.