Montana, unlike many other states, does not take away your state gun rights if you did not use a firearm in the commission of your domestic violence offense. The problem, however is not with Montana. It's with the Federal government.
Under the Violence Against Women Act and the Lautenberg amendment, a conviction for a misdemeanor crime of domestic violence will cause you to forfeit your Federal gun rights for life, regardless of whether a firearm was used in the offense.
If you had to take a plea to get your suspended sentence, the Federal government will take that as a conviction for purposes of your gun rights.
That means, even though Montana would not prohibit you from owning and possessing a firearm, under the right circumstances you could end up charged by the Federal government were you caught by Federal authorities with a firearm. The fact that you still have Montana rights would not protect you.
You can see the Federal definition of a crime of domestic violence below. If your conviction doesn't take in those elements, you would still have your Federal gun rights, and you'd be okay under state and Federal law. But if the case for which you were convicted conforms to the Federal definition, there is nothing you are going to be able to do unless/until the law changes.
For purposes of its unlawful gun possession statute, the Federal government defines a misdemeanor crime of domestic violence in 18 USC 921. The statute says:
"the term misdemeanor crime of domestic violence means an offense that:
(i) is a misdemeanor under Federal, State, or Tribal law; and
(ii) has, as an element, the use or attempted use of physical force, or the threatened use of a deadly weapon, committed by a current or former spouse, parent or guardian of the victim, by a person with whom the victim shares a child in common, by a person who is cohabiting with or has cohabited with the victim as a spouse, parent, or guardian, or by a person similarly situated to a spouse, parent, or guardian of the victim."
Without Federal rights, you will not clear a NICs check, nor will you be able to get a carry permit. So unfortunately, until Federal law changes, you'd essentially be without rights indefinitely.
I am sorry to be the bearer of bad news, but hope that I have clarified the law as to these types of misdemeanors.