Yes you can but you will need the Affirmation Of Marital Status from your consulate/embassy in Thailand and need an interpreter during the registration for marriage certificate process.
Jason Tolputt the visa called K1 fiancee visa have a look. after you get married with her, you will need to file her green card and work permit. it will take at least 6 months to receive. during the time she waits for her documents she won't allow to work
you are not supposed to change the flight closer. You can only postpone it. But I begged the LA consulate. I really mean by begging. His flight got cancel so many times that he was about to give up. Without begging to get it I had no choice. It worked out great