In re Marriage of Culm, 2025 IL App (1st) 240566

Summary

Case Summary: In re Marriage of Culm, 2025 IL App (1st) 240566 - Under In re Marriage of Culm, Illinois courts require proof of shared domicile and financial interdependence—not merely a romantic relationship—to terminate maintenance for cohabitation "on a resident, continuing conjugal basis." Separate residences, no joint accounts, and no shared property ownership defeated the termination petition despite evidence of long-term dating, overnight stays, and frequent monetary transfers between the parties.

The opposing counsel is already on the back foot—because they thought a few romantic getaways and some Venmo transactions would be enough to kill your client's maintenance obligation. The First District just handed down In re Marriage of Culm, and it's a masterclass in what actually constitutes cohabitation under Illinois law. If you're litigating maintenance termination in Cook County or anywhere in this state, you need to understand why Geoffrey Culm lost—and how to avoid his mistakes.

The Setup: A Relationship That Looked Like Cohabitation (But Wasn't)

Geoffrey Culm came to court with what seemed like a compelling narrative: his ex-wife Alice had been in a long-term relationship with Michael Kolander. They traveled together. They exchanged gifts. They had an intimate relationship. There were overnight stays and numerous small monetary transfers between them. On paper, it looked like the kind of arrangement that should trigger maintenance termination under the marital settlement agreement and 750 ILCS 5/510(c).

But here's where Geoffrey's case fell apart: dating is not domicile. The trial court found—and the appellate court affirmed—that Alice and Michael never established the hallmarks of a de facto marriage or shared residence. They maintained separate primary residences. No joint bank accounts. No shared ownership of property. No joint mortgage or lease obligations. No beneficiary designations naming each other. No mutual tax disclosures or shared household financial obligations.

The First District treated this as a factual determination and applied the manifest weight of the evidence standard. Geoffrey couldn't clear that bar because he never built the evidentiary foundation required to prove cohabitation "on a resident, continuing conjugal basis."

What the Statute Actually Requires

Section 510(c) of the Illinois Marriage and Dissolution of Marriage Act doesn't terminate maintenance just because your ex has a boyfriend. The statute requires cohabitation on a "resident, continuing conjugal basis"—and courts interpreting this language demand proof of something that looks and functions like a marriage, minus the certificate.

The Culm court emphasized that the dispositive factual issue is whether the parties were living together in a manner constituting a shared residence and conjugal household. That means you need evidence of:


Shared domicile: Same address, shared mail, joint lease or mortgage, utility bills in both names
Financial interdependence: Joint accounts, shared credit, commingled assets, mutual financial obligations
Public acknowledgment: Holding themselves out to family, friends, and community as a married or quasi-married couple
Domestic integration: Shared household responsibilities, estate planning that reflects the relationship, beneficiary designations


Occasional overnight stays, vacations, and romantic dinners don't get you there. Neither do Venmo payments for splitting restaurant bills or birthday gifts. Courts are looking for the infrastructure of a shared life—not the trappings of a dating relationship.

The Pleading Problem: Survive 2-615 or Go Home

Geoffrey's case also highlights the importance of pleading sufficiency. If you're filing a petition to terminate maintenance based on cohabitation, your amended petition needs to include specific factual allegations: dates, addresses, acts demonstrating shared residence. Vague assertions that your ex "is living with someone" won't survive a section 2-615 motion to dismiss.

Your pleading should read like a roadmap to the evidence you intend to present at trial. If you can't articulate specific facts supporting cohabitation at the pleading stage, you're signaling to the court—and opposing counsel—that your case is built on speculation rather than substance.

Discovery Strategy: Where Cases Are Won or Lost

This is where sophisticated practitioners separate themselves from the pack. If you're pursuing maintenance termination, your discovery needs to be surgical and comprehensive:


Subpoena records: Bank statements, credit card statements, utility bills, lease agreements, mortgage documents, property tax records
Digital footprint: Social media posts showing shared residence, location data from devices, shared streaming or subscription accounts with the same billing address
Third-party depositions: Neighbors, landlords, family members, employers who may have knowledge of living arrangements
Financial discovery: Tax returns showing address, insurance policies, beneficiary designations, estate planning documents


Here's where the cyber-law angle becomes critical: in high-net-worth divorces, digital evidence is often the smoking gun. Shared passwords, joint cloud storage, family phone plans, smart home device logs—these all create a documentary trail that proves (or disproves) cohabitation far more effectively than witness testimony about who slept where.

And if your opposing party has been sloppy with their digital security? That's leverage in discovery. Metadata doesn't lie, and neither do login records.

Defending Against Termination: The Culm Playbook

If you're on the other side—defending a client's maintenance against a cohabitation claim—Culm gives you the blueprint. The court was unmoved by evidence of:


A long-term dating and sexual relationship
Shared trips and social activities
Occasional overnight stays
Gift exchanges
Numerous small monetary transfers


What mattered was what wasn't there: no shared address, no joint accounts, no joint ownership, no mutual financial obligations, no public acts demonstrating they held themselves out as husband and wife to family and community.

If your client is in a relationship but wants to preserve maintenance, the guidance is clear: maintain separate residences, keep finances separate, avoid joint ownership of anything significant, and don't hold yourself out to the world as a married couple. Document the separation of your lives as carefully as you'd document any other legal position.

Drafting Better Settlement Agreements

The Culm litigation could have been avoided—or at least streamlined—with better drafting at the settlement stage. If you're negotiating a marital settlement agreement with maintenance provisions, consider:


Defining "cohabitation" with objective criteria: Specify what constitutes cohabitation (e.g., residing at the same address for a defined number of nights per month, sharing household expenses above a certain threshold, joint ownership of property)
Procedural mechanisms: Include notice requirements, temporary suspension provisions pending determination, and clear burden-of-proof allocations
Verification rights: Build in the right to request documentation (tax returns, utility bills, lease agreements) on an annual or semi-annual basis


Ambiguity in settlement agreements breeds litigation. Precision prevents it.

The Appellate Standard: Why Deference Matters

Practitioners need to internalize this: trial courts' factual findings on de facto marriage and cohabitation receive substantial deference on appeal. The manifest weight of the evidence standard is a high bar. If the trial court found the facts against you, you're not getting reversed unless you can demonstrate that no reasonable person could have reached that conclusion.

That means you need to win at trial. Build your evidentiary record meticulously. Don't assume the appellate court will save you from an adverse factual finding.

Strategic Takeaways

Culm reinforces what experienced family law practitioners already know: maintenance termination based on cohabitation requires rigorous proof of residential and financial integration. Romantic relationships—even serious, long-term ones—don't automatically qualify.

If you're pursuing termination, you need documentary evidence of shared domicile and economic interdependence. If you're defending against termination, you need to demonstrate the absence of those factors. Either way, the case is won or lost on specifics, not generalizations.

The First District has drawn a clear line. The question is whether you're prepared to litigate on the right side of it.

If you're facing a maintenance dispute in Illinois—whether you're seeking termination or defending against it—you need counsel who understands the evidentiary requirements and strategic positioning that determine outcomes. Book a consultation now. Your opposition is already making mistakes. Let's make sure you're not.

Full Opinion (PDF): Download the full opinion

Written by Jonathan D. Steele

Chicago divorce attorney with cybersecurity certifications (Security+, ISC2 CC, Google Cybersecurity Professional Certificate). Illinois Super Lawyers Rising Star 2016-2025.

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