My fiancee went with me to the bkk bank. Last year. With the paperwork that they require. Was pretty easy. Sold me some insurance. 5000 baht. Which they cancelled later. Said i did not require.
We were successful last year. Used an agency to ensure we were successful. Lots of evidence of our 5 year relationship. Her company were very good letting her have time from work. Had 45 great days in the uk.