I guess I just don't know what signs to look for that you are "fully accepted" but that's OK. Nobody presents you with a plaque saying "You Are Hereby Fully Accepted In Our Society". Also, I'm a bit of a loner by nature. I don't really
want to be out chatting with other people most of the time. There are some Japanese people (most are 100% fully Japanese in every definition of the word) who are afraid to go outside. They call them
hikikomori. It's like a kind of social anxiety. I wonder if they feel "fully accepted" even in their own society. But I work for a Japanese company and I commute to work every week day and I've almost never encountered overt hostility. I'm sure that I'm "fully accepted" at my company. But it's hard to really know. I imagine that there are some places in Japan where I would not be welcome, but I must imagine that there are
places in the UK that don't care much for foreigners or "outsiders" coming in.