Hi Roman. It’s quite a long and difficult process to get a Thai passport. However, you have a type O visa which you can convert to a Thai marriage visa. This is renewed once a year . You will have to show where you live and a bank statement showing at least four hundred thousand baht. The complete details are on the Thai embassy website.
After one year you have to re apply for your marriage part of the visa. This is done in Thailand and is just a case of checking your documents from the original application. They are checking that your circumstances haven’t changed ie. that you are still married, have 400.000 baht in the bank. No need to leave Thailand every three months. Just report to immigration.
Initially, you get a type O visa and you have to leave Thailand to get this visa. On return you have three months to convert the type O to a marriage visa. The marriage visa is valid for one year from date of issue. The marriage visa is renewed every year without having to leave Thailand.
Not worth getting stressed over any visa problems now. The situation with the coronavirus has created mitigating circumstances for all farangs’. Send an email to your local immigration office briefly outlining your personal visa difficulty. Keep a copy of your email with the date sent included. Most important, obey the social distancing/ curfew/ lock down rules.