I never got to like standard soy milk, but the unsweetened soy milk is OK. It's good in cooking (e.g. I use it to make jalapeno and sweetcorn chowder). To avoid it curdling in coffee (if using instant coffee) mix the milk with the coffee first, stirring well, let the water cool down for a minute or two after boiling before you add it. With filter coffee, I guess let the coffee cool down before adding it, probably best to put the milk in the cup first and gradually add the coffee to the milk, with lots of stirring, rather than adding the milk to the coffee.
Wow, Western China! That sounds pretty exotic and adventurous!
In some ways I imagine it's quite hard to stick to the OMS diet over there. In other ways it might be easier if they haven't let dairy creep into the indigenous diet yet (I'm thinking of the China Study where I know many regions had very little dairy). One other possibility is to make your own nut milk. I admit that I haven't done this myself, because I have a Sainsbury's and a Tesco down the road, but I have seen demonstrations online for how to make your own nut milk. It looks pretty easy: put almonds (or other nuts) and water into a blender and blend.