If your spouse signed a formal agreement resolving all the issues, the judge may or may not allow your spouse to wriggle out of that agreement and contest one or more issues in front of a jury. If it comes down to a jury trial I HIGHLY suggest you hire a lawyer to help you with your case, even if it's just coaching you on rules of evidence and courtroom procedures if you insist on representing yourself.
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You may possibly have badly screwed up. Very badly,. Get a lawyer ASAP.
As a general rule, the filing of a divorce REPLACES the separate maintenance case, and unless there was specific language in the agreement that allowed you to also use it in a divorce, there is a strong possibility, especially if circumstances have evolved and changed, that a judge may not enforce the agreement now.
Since she has a right to seek a jury trial you need a lawyer. I have had cases where with good pleadings I can strike that demand because of no answer, but that's probably an amendable defect, so the case would still go to trial.
Again, get a lawyer. It's vital in your fact pattern.
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