A.N. Prompt from Wordwielder: Post-Christmas depression.
Not exactly sure about the conclusion, but forgive me. I'm not so good at cheering people up (I'm usually the depressed one), so...
Holmes' point of view
The first Christmas after Watson and I had begun to share lodgings had just passed, when my flatmate's mood turned to worse. I was used to my own depressive fits, and advised Watson to just ignore me when I got like that. After all, I developed my own way of coping (even if the doctor didn't like it) and the very existence of Inspectors like Athelney Jones and Gregson was my guaranty I wouldn't get swallowed by it whole.
However, ignoring Watson's gloominess requested a considerable effort. I had no data to work with, so I had no idea how soon – if at all – this was going to vanish. It worried me. I wasn't used to worrying for another human being – not since Mycroft had carved his own niche – and it was unsettling. Or, to be more precise, I worried a lot about my clients – especially if their life was in danger and an attempt against it was foreseeable – but in such occasions I was in a flurry of activity to stop the culprit. Worrying without knowing how to help was quickly becoming unbearable, so I did the only thing I could. I set out to get more data.
"Watson" inquired I one evening "whatever is the matter, old boy?".
He tried feigning ignorance of what I was asking about. Naturally, I didn't let him such an escape.
"It's all so stupid" he finally confessed "and...petty, I guess. I had so much hope for this holiday season...I thought my friends would show up, that even if my family is gone, we could have a big celebration, like I was used to in the past...instead, almost no one contacted me. As a result, I've gone to public places, since the crowd there was better than nothing, and as a result I've wasted a lot of money. I should have known better. I'm disappointed in my so-called friends, in myself...in everything. I'm sorry if my behaviour has disturbed you".
Well, now I knew how to stop the thing from repeating itself. I wasn't exactly a social butterfly, but if all Watson wanted was having people around, I could enlist the Irregulars. He had quickly warmed up to the boys, and they liked him. Like anyone mildly compos sui, may I add. Mrs. Hudson would surely see the worth of having the house full of admittedly wild kids rather than a depressed doctor later on. As for right now...
"You didn't disturb me" I stated, even if I did not say what he had truly done "but please, Watson, let the past few days go. Together with your friends, I'd advise, since that definition looks in need of a severe revision anyway. So what if you've blundered? You're human, and money can be as quick to come as it is to flee, sometimes. You could try making an hobby into a job – or side-job, in your case – if you need one. It worked well enough for me".
P.S. Compos sui is Latin, it means literally "master of one's self" but the true meaning is "of sound mind".