If she really wants the divorce and she's not just throwing a tantrum then set a date with her to go down to the local district office and give it to her. At the end of the day it's her choice and her right. Especially if you have no dispute over assets. It's a super simple process if you both agree. If you are currently on a non-O visa based on marriage technically it should be cancelled 24 hours after the divorce. But the systems aren't linked and the responsibility is on you to cancel the visa. However as with anything in life there's a grey area and I'm speaking from experience "I had a friend". If you don't report it you can just let your visa run it's natural course and then get a new one. My last point and it's non of my business. But if she doesn't want you then you really should move on and find someone who actually wants to be with you. It's not as if there's a lack of choice
No if you got an extension within Thailand you have until the stay permitted date stamped into your passport. Also if you leave without obtaining a reentry permit the stamp is no longer valid. If you got a Non O at the embassy outside of Thailand you can come back in 1 day before your visa expires and get an additional 90 days. If you have a Non OA it's an additional year
The airport is very far from the city and with Bangkok traffic it would be very risky to do via taxi. You can take the airport link and connect to the sky train but unless you know what your doing it will be time consuming. The airport isn't too busy these days do when you get back you could clear security and immigration quickly but you don't know if there is a big tour group ahead of you.
