I'm not asking this question in the sense of how others perceive you, in a homogeneous country like Nepal a Westerner will always be an outsider even if you live here the rest of your life and speak the language fluently. I'm asking the question more on a personal level, as in when do you stop seeing things as a tourist, and come to regard those things that once struck you as so different or breathtaking as just an everyday occurrence?
For me it seems to have happened around June. I can tell because I try to carry my camera in my pocket all over, and I would take pictures whenever something struck me that I or someone back home might want to take a look at. After May I ended up just lumping my pictures into a folder called "summer" because there just isn't enough of them any more. I mean sure the random cows in the road catch me off guard once in a while, but not like they use to, and I never bother to take a picture any more. It use to be that the Bollywood and Nepal Movie posters would get me laughing out loud at their absurdity and horrible photo shopping, but now only the very worst ones catch my attention. The other day while passing a temple during Krishna's birthday there was an elaborate ceremony and music, and though I stopped for a minute to watch some woman dancing and children running around all dressed up, it again didn't occur to me to take a picture. Every other day here seems to bring a new holiday and Nepali's seem to dance at every one of them!
The point I am getting at is that despite how different a place might be from where you are from there comes a time where it just starts to not seem so exotic and strange. Do I consider myself a local? Absolutely not, but I do consider this my home at the moment and I certainly feel very comfortable around things that many of my fellow countrymen would find quite odd. A country like Nepal especially causes a certain amount of culture shock among people from the west. The food is very different, the mindset of people is very different, the driving is different, the religion is very foreign, the dress codes seem very confusing (Little skin should be shown meets public bathing), the bathrooms are odd, water is heated by the sun and electricity comes and goes. All of this and much more adds up to something that can catch you a little off guard. At this point though, I don't even think about it most of the time. In fact as i write this I have no electricity aside from my little back up battery, but I didn't really think about it much until I typed the previous line.
Sure some things you never really get use to. I still find the skin whitening creams really creepy. Even though it is not meant to be rude, the disregard for lines, and the constant cutting off of people or other actions that are considered extremely discourteous in the west really can at times put you out if you forget where you are. Dudes holding hands and putting their arms around each other still strikes me as rather gay (not that there is anything wrong with that!), even if supposedly it isn't here (although I would submit that there is a lot of homosexual behavior that goes on here and the guys just don't consider themselves gay...just like the middle east). Anyway my point in all of this is that it doesn't all exactly make sense to me, but it also doesn't strike me odd anymore. You expect it, you know what you are in for most of the time.
Maybe in the end that is what seperates the tourist from someone who feels at home. As a tourist you are always waiting to look at and experience new things. The most mundane things to the locals seem like the most exotic and spectacular things to a tourist. There is a quote by Dagobert D. Runes that, "People travel to far away places to watch, in fascination, the kind of people they ignore at home." This is I think true, though it is not just people. It is architecture and landscapes as well. We always fail to see what is around us every day as anything special or amazing. When that sense of wonder at your surroundings fades, you stop seeking out to look at things as a tourist, you walk by them and say to yourself, "Should I go left or right to get around this cow in the road."