Many more farang deaths in central thailand than the south, so statistically youll be fine. But then again, there arent as many farangs in the deep south as central thailand. Dannok, Hatyai, Padang Besa, Satun, Betong should be as safe as anywhere else, if not safer.
Its better to do so to be safe, but new passports will have a stamp stating that so and so previously travelled on xxxxx (your old passport number), so it is very easy verify.
No you cannot. You will have to leave the kingdom to get a Non Immigrant O/B at the nearest thai embassy. The problem is you cant switch to an O or B within the kingdom.
It was all fun when both of you were travellin and goin places huh? Get the divorce settled quick, divorce her before she divorces you. You deserve better Terary.