Keeping a record, and why it helps twice
A journal, a timeline, and a page about what you actually want. One of them supports your case, one supports you, and mixing them up causes problems.
Writing things down is standard advice in a divorce, usually offered as though there were one kind of record. There are three, they do different jobs, and the useful move is keeping them separate.
Because here is the thing nobody mentions: anything you write about the case may eventually be read by other people. Your attorney, possibly the other side, possibly a court. The private processing you need in order to survive this is not the same document as the factual record that supports your position, and combining them means the most raw thing you ever wrote arrives attached to the most consequential.
So: three records.
The factual log
What happened, when. Dates and times, what was said or done, what was decided, what money moved. Short entries, close to the event, without adjectives.
This is the one that earns its keep. Memory under stress is genuinely unreliable, and months later you will be asked specific questions about specific days. A contemporaneous note is worth far more than a confident recollection, both to your attorney and to a court.
Write it as though a stranger will read it, because one might. That means facts rather than characterization: "did not arrive until 7:40, second time this month" rather than "was late again, as usual, because he does not care." The first is evidence. The second is an argument, and it undercuts the first by making the whole document look partisan.
Keep the underlying material too. Texts, emails, and voicemails, saved somewhere outside the shared house and outside any account your spouse can reach. How messages and screenshots are actually treated in court covers preserving them in a form that holds up, and the one way of obtaining them that can be a crime.
If there are threats or harassment, this log becomes something more serious, and it may support a protective order. Keep it meticulously and tell an advocate or your attorney it exists. The safety resources page has the numbers if that is your situation.
The private journal
How you are doing. Not events, feelings.
This one is for you, and it does real work: it is the thing that makes therapy more useful, it shows you patterns you cannot see day to day, and it gives the three-in-the-morning thoughts somewhere to go other than round in circles.
Keep it genuinely separate from the factual log, and know the actual rule: a journal can be requested in litigation if it is relevant to the case. What you tell a therapist is privileged in every state; a private journal is not, and the privilege does not reach it. That is not a reason to avoid journaling, which helps too much. It is a reason to keep the raw material apart from the record you intend anyone to read, and to ask your attorney if you are ever worried about it.
The marriage timeline
Once, not daily. A factual account of the relationship: when you met, married, moved, had children, bought property, when either of you stopped working or started, the turning points.
This exists because your attorney will need it and reconstructing it in a billed meeting is an expensive way to remember your own life. Dates for residency, the separation date, when assets were acquired, and how long the marriage lasted all key off it, and all of them affect outcomes. If you have been keeping the factual log, the timeline is mostly assembly.
Note where the two of you might disagree, particularly about when the separation actually began. That date can determine what counts as marital property, and if there is a genuine dispute about it, recording your version now with whatever supports it is far better than arguing from memory later.
The one about what you want
Different again, and the shortest. A page on why you are doing this and what you are trying to end up with.
Two reasons it is worth writing. It makes you a much better client, because "time with the children matters more to me than the retirement account" is something your attorney can act on, while "I want what is fair" is not. And it is an anchor: divorces drift, positions harden over things that turn out not to matter, and a document written before you were exhausted will tell you what you actually cared about.
Revisit it rather than treating it as fixed. Changing your mind on the record is fine; drifting without noticing is what costs money.
Practical
Keep all of it somewhere that is yours, not in shared cloud storage or on a shared device. If you have been sharing accounts, set up new ones first, and see the digital separation guide for the order.
Date every entry. Write close to events rather than reconstructing weeks later. And do not curate the factual log to look better than reality, because a record that omits the inconvenient parts is worth nothing the moment one of them surfaces.
Whether personal writing can be requested in a case, and how a separation date is established, vary by state. Ask a licensed family-law attorney what applies where you live, especially before relying on a record in a dispute.