Mediation Matter
This is a disagreement between the initiator Anna and the co-participant Mark, who live as partners in Cromwell with their 3-year-old son. Anna expected that Mark would notify her about his delay in arriving home, while he admits that he could have done so, but that work 'carried him away'.
Assessment
Both agree that timely notification would have been expected and respectful. Anna had reason to feel overlooked, as she relied on the agreed time. Mark, however, did not act with the intention to hurt – he simply became absorbed in his work and forgot to communicate. This is a minor breach in communication, not systematic disrespect. Anna is not at fault for expecting the agreement to be respected; it is Mark who created uncertainty.
Mediation Opinion
I suggest that Mark offer a sincere apology to Anna for not informing her about the change in time – not because he 'could', but because it would have spared her worry. I also recommend that they agree on a simple way of notifying each other (e.g., a short SMS for any delay), which will make life easier for both. Financial compensation is not appropriate – this is about mutual respect, not material damage.
Concluding Remark
When work 'carries you away', I imagine you are riding a train without a watch – but since you probably already have a watch at work, you could find two more minutes for a message before you are carried away until 5:30 PM. Next time, perhaps rather tie your phone to your hand – or remember that 'I'm coming at 3 PM' is a promise, not a train reservation that you can miss without penalty.