In America...
Write up a contract so that everyone understands the rules.
Don't get a marriage license except if you want government to partake.
If there is a breach of contract, take it to court - Judge Judy court style.
If you do it this way, and if one of the marriage partners takes it to court in the standard way, the other partner resists by filing HIS/HER case right on top of and in the other case. The second case is filed Judge Judy style, and is based on the idea of, "Show how I have broken the contract. If you can't, you are breaking the contract. I require damages in the amount of XXX." The base amount can be written right into the contract at its start.
A Judge Judy court is a court of record. The judgment is either a judicial judgment or a jury judgment. Attorneys are not involved except for advice outside of court if desired. Try to make it work one way or the other outside of court.
Worst scenario for the one who is being divorced by the other in this case is an equal split of property and visitation. Best case is, the marriage is retained.
fml.
