The govt. licenses marriage and thus the govt. controls marriage.
Look at divorce: who gets what isn’t decided by a church, or the couple, or any concept of sacramental bonds, but rather by govt. courts.
Exactly correct. The government decides. If one desires a divorce through the Catholic Church, one must go through a church annulment process. If you do not and begin dating or pursue a civil marriage outside the Church, one is living in sin.
The legal and the sacrament are separate concerns.