Is OTHER wrong in the post ? POST : I've been at my job for a little over a year, and for the first couple months one of my co workers and I were relatively friendly. Exchanging pleasantries and asking about each others weekends. Not to the extent that another co worker and I are friends and always joking around, but friendly enough. 
After a couple more months it got to the point were he would stop by my desk while i'm clearly busy working and start chatting. He did this several times a day, often starting with the question "Busy?" to which I always answered "very busy!" and then would continue to drone on. 
One day he stopped by and proceeded to ask me questions about my marriage followed by 40 minutes about his relationship and all the trust issues he has with his new girlfriend because of his ex-wife. 40 frikin minutes.
The next day I decided I'd had enough and stopped talking to him outside of a "morning!" when I walk in and "have a good one!" when I leave. When he asks conversation starting questions about my weekend or life I give him one word responses and don't ask after his weekend, which he is so clearly fishing for. He eventually started to get the message, and mostly doesn't talk to me anymore. He even seems to be scared to ask me about work related things. 

Apparently he is now going around the office chatting to other people while they're trying to work. and people are annoyed.

I feel like an asshole, mostly because when my other co-worker comes by, we chat and joke around, although we do so while we're working on things together. And I'm worried it's coming off as high school assholery.

So, Am I the asshole?