My boyfriend has just been arrested for what I though was a probation violation, but the violation was breaking his restraining order against his ex. He didn't not contact her she was the one that contacted him but he made a statement to her, but when I look up his inmate information and it said Motion to Adjudicate Guilt that's is where I got lost I don't understand why he is in jail?And how long will he have to stay in jail?

This motion is normally filed when the state is moving revoke ones probation.
The state files an application to proceed to final adjudication. That means to find one guilty of the crime they were originally charged with and placed on probation for.
When the state proceeds to adjudicate they are moving to find the individual guilty of the offense and most likely revoke his probation. (Wiki)

It basically means there is going to be a hearing before the judge. The judge will decide if the state will enforce the original sentence.. Lets say boyfriend was sentenced to 5 years in jail, but it was suspended and given 5 years probation. So probation revoked and he goes to prison for 5 years.

It will deal with the violation of the restraining order. If boyfriend talked to and communicated with someone, who there was a restraining order to stay away, he should have known better. Even if the other person started. If he has evidence that shows the other person started it. ( phone records perhaps showing they called him)
It may help