In Norse mythology the winter solstice is when the wheel of the world is at its lowest point. In this liminal time of the year the veil between the living and the dead is thinnest, but also the gods are closer. All but the evergreen trees had the appearance of death, and yet in the midst of this was a celebration, because even in the literal darkest of days there is hope of light.
The seasons circle relentlessly, driven by the position and movement of the earth in relation to the sun. Growing up in Missouri I had four distinct seasons to count on, and I couldn't imagine living somewhere without a leaf-laden fall or a frosty winter. Then when I lived in Brazil I learned that it's not just a single uninterrupted climate there either. In Uberlandia, in the high savanna, I could count on July to give us a week where temperatures could drop into the upper 40s, and that August would be windy. In December going into January there was more rain than usual, and I even planted a garden one year on Christmas Day.
As with the seasons, so with our lives. We are not exactly as we were yesterday, and tomorrow we will not be entirely the same as today. Taking it further, what seemed most urgent to us 10 or 20 years ago is old news now, if it is even remembered. Any time I feel that I'm too nostalgic for the past, I try to remind myself of the very real worries I had at the time, without trivializing them based on the improved perspective I have now.
What presses on you most right now, and how do you think it might look to you in 10 or 20 years, assuming such time is available? You might at that time see that you were a survivor, and admire your strength. You might feel compassion for your past self, understanding how terrible things were. It's hard to say, but for a certainty this phase of your life will have passed. Perhaps you can put yourself in that mode of future perspective, look at yourself now, and find some compassion and admiration to carry you along.
The wheel is turned to the lowest point, but from here on the cycle takes us back up again into the light. That is one of the few guarantees this world gives us, a promise kept year after year.