My birthday was a couple of days ago, and my schedule was so tight, that I didn't get to celebrate it as I usually do, with my friends. It wasn't so bad, though I do was quite tired, what with work and then the German classes. but my coworkers got me a cake (and eggnog cake!), and then, when I got home I had a galss of wine for myself. Honestly, it was wonderful. I was alone in the kitchen, at night, with a glass of wine and feeling so incredibly self indulging, it was wonderful. Little after, I thought how there's people who get depressed for this very situation. For me, it was beatiful, fantastic and the type of experience I want to have more of. It's not the first birthday I spend celebrating alone, and these both experiences remain in my mind as amazing ones.
Every experience affects you in the way you choose. Maybe you are sad because you choose to see things that way. Maybe. In any case, it's worth thinking about that.