As humans of female chemistry, we join the female side of the statistics. One of the downers of being female is being much more prone to depression in all of its forms.
Seasonal depression is very common in the higher lattitudes and in night shift workers, and comes from the lack of bright light exposure that controls our bodies' internal clock, sleep cycle, and moods. Some people are just more sensitive to the seasonal changes in light, women more than men, and their whole neurotransmitter system gets thrown out of balance by the lack of clock reset each day. The depression is like a permanent bad case of jet lag. Treatment? 15 minutes each morning (or the time of day you wake up from the daily sleep if you are a shift worker) of very bright broad spectrum light has powerful effects on those with SAD (seasonal affective disorder). Light boxes that do the trick are widely available and start out around $100 but you can spend a lot more. My older sister has it, and her annual depressions went away for good when she started religiously using a light box while she read every morning. It runs in families, but hits the women more often than the men.
Other kinds of depression that get worse this time of year, and hit women harder than men, and hit trans women harder than cis women:
The depression you feel from social isolation, when you are going through the time of year that represents the dream of belonging in a loving relationship and having a loving family around you. "No one should be alone at Christmas".
The related depression from grief, for the loved ones that used to be with us who no longer are.
The related depression from unrealized dreams and fading hopes. Gender dysphoria often turns into depression as we see people who have everything we want to have, go about their lives as we would wish to do, and that seems so far away for us that it gets us very down.
All that said, you are doing the right thing Medusa by reaching out to others. SAD is easy to fix with light exposure, for the rest, its exposure to people who believe in you that does the most for me. Self care includes not only grooming our hair, skin, and clothes, more importantly it includes making sure we talk to ourselves in kind and non-defeating ways, and take steps to connect with other kind positive people who may also be struggling.
Hugs!*
By the way, that's not just an expression. Touch is enormously powerful in alleviating depression. Cuddles, hand holding, hugs, neck rubs, massages, even getting a good manicure or pedicure.... women constantly touch each other, because it feels good, and except for those on the autistic spectrum, we all need and crave it. Unlike for guys, it doesn't have to be sexual at all. Touch, touch, touch.
And if you are like me and old fossil feelings of sadness and loss come to the surface, love yourself and tell yourself 'I am feeling sadness and loss (or whatever feeling it is). The things that caused me to feel this way, happened." Then ask yourself 'What message do these feelings have for me at this time?' and listen to your heart. It might be, 'I miss having someone to talk to at the end of my day, and cuddle up next to when the weather turns cold and grey'. Listen to your heart again, and just feel the truth of your answer. Then give yourself a choice statement. For example, 'I chose to look for opportunities to connect with people who are like me, and to be patient with these feelings and myself'.