I am not sure when living alone became a disgraceful sign of being a total worthless loser as implied in so many posts. Anyway ...
In a legal sense, the vast majority of Expats here in Thailand "live alone." Only a small percentage are married, and have the foresight to write and register their last will and testament, with the corresponding recipients and documentation to facilitate a smooth transfer of assets after their death.
Example: You have a long term girlfriend who you feel is, and treat as ... "your wife." For lots of complicated tax, income, and cultural rules, you find it much easier to just stay "single" and have a happy life. You live in Thailand via the "retirement visa" and keep the required 800,000 THB in a bank to ensure compliance and easy annual renewal. You also have your "other" account for living expenses ... etc. You may even own stocks in the SET, since there is no capital gains tax in Thailand, and there is money to be made.
You drop dead tonight. Who has the legal rights to your money?
Does your girlfriend have a legal right, via an official Last Will and Testament to begin the rather lengthy process of getting the money and stocks you meant to leave for her? Does she even know the process to follow?
Oh wait, you think she can just transfer the funds to her account? Have you updated your banking transfer values to allow that, or will she hit the new fire wall of "transfer of funds requires face recognition." Have you considered a request to transfer your 800,000 is a red flag in the banking system. since it implies "This person has just disqualified themselves from the Non Immigrant O process." Golly, we should look into this.
The point is. Thai banks make a TON of money KEEPING Expat funds, and forcing those left behind to hire lawyers, and engage in protracted legal battles. More often than not, the very person who needs the money, can't fight that battle, and would not know where to start.
Feel free to message me for ideas that can help.
(PS: Don't let me "newbie status" fool you, there is a good chance I have lived in Thailand non-stop ... longer than you)