You are absolutely correct -- it's not sustainable to stay on guard forever, and I can feel real damage being done with every moment I feel I have to watch my back. Which is why I won't be just taking a time-out, but getting out of the situation entirely.
I'm currently in the process of preparing to move back home to my own country, so that I can be in a situation where I am surrounded by people I can be more open with. It will take several more months before I can make the move (I've been here for almost 15 years, so uprooting is a long, tedious process), but I am already feeling much better knowing the end is in sight.