Hi Babi,
I've been couple of times to Bangkok (for short business stays). I have not found any proper veg*n restaurant, but I could find suitable food in the mid-level restaurants (either thai, japanese or italian). The best is when they speak English (not always the case), then you can discuss and they can adapt something for you. Most Thai people eat on the street, but this is always meat-based and no way to discuss if you don't know the Thai language. I had assumed many Thai would be vegetarian since this is a Buddhist country, but they don't seem to have a problem with eating animals...
Otherwise, to answer the subject ( "where have u been?" ), I've been to many places. Not always easy to find veg*n food, but almost always managed. As a vegetarian, the best place I have visited is Taipei.
Cheers, Frank.