You dont need an ED visa to study at any language school, you can arrive on a tourist visa(60 days) then extend it(30 days), rinse and repeat with another tourist visa from a neighbouring country. This gives you 180 days in Thailand.
You wont need a 'work visa', you can apply for a work permit and legally work on your Non Imm O visa based on marriage and its subsequent extentions of stay.
The OP doesn't really give enough info for visa advice, I was merely pointing out that you can enter Thailand via a land border as many times as you like per calendar year if you have a visa. It's only visa exempt that is restricted to two land border entries per calander year!