Big congrats on 10 months-awesome! I think the holidays are hard because it's a lot of forced emotion all at once. There is pressure from the media and other people to create this perfect holiday. You're feeling stressed if you're trying to create it, and depressed if it's not happening. Lonely feels lonelier this time of year. Everything emotional gets exaggerated and when it's happening to everyone all it once there's drama, sadness, anger, joy, you name it. All kinds of family things get dredged up. It can be overwhelming for anyone. Trying to go through it while recovering is even more difficult.
You're right, it does pass, and your post was encouraging and thoughtful.