I just went on the thaievisa website to go through the motions of starting the visa applications. For "Purpose of visit", did you select "Visiting or staying with applicant's family resided in Thailand (more than 60 days)"?
Right now the embassy website is saying I need 3 million baht or US$100,000 annual coverage. So far in the US I pay all my medical and dental out of my own pocket, so I consider it worthwhile having insurance for accidents and major medical, but I don’t intend to file a claim for every little clinic visit or dentist appointment, other than for meeting my deductible. I closed my AmEx accounts but I’m wondering whether it would be worth applying for a new card. Have you ever filed a claim?