Music is the first thing that comes to mind when hearing the word rhythm. A cardiologist would disagree claiming that heart rhythm should be first to mind. The linguist might argue that cadence or routine or flow are more powerful descriptors to use.
No matter who you side with, the regularity and consistency of a continuous beat or output or ritual can be very comforting. Waking up in the morning and exercising first thing, followed by breakfast than reading and so on. Everyday doing the same three things to begin each workday. There is a calming effect to being in rhythm that goes unnoticed on many days.
Interruption, crisis, or even uncertainty easily destroys rhythm. Especially when it is our mind and focus that is stolen from us in the heat of the moment. The issues that arise linger in our hearts and minds surrounding us in a deep fog far from the shore of clarity.
I find that seeking a rhythm to parts of our day can help immensely. Organizing one or two hours into a series of rituals that bring us consistency and comfort. It can be as simple as never leaving the house in the morning until you fix your bed. Or never leaving for work until you wash your breakfast dishes.
Especially when you feel most tense and unsure. Seek things that you can easily do and then do them again the next day. While this will not solve your problems, it will give you a chance to feel in control albeit for just a small part of your day. Helping to bring you a subtle awareness that you still are ok in the midst of your battles.