“Self custodian wallet”…

I guess that’s another way to put it. Sounds strange to me as I’m used to calling it non custodian wallet.

@OP, i would recommend Electrum wallet for you for a non custodian wallet or you could use Mycelium. Virtually a wallet that gives you a private key or seed phrase would be cool.

You could as well get hardware wallets or store in air gapped wallets (wallets that haven’t gone online by any chance). You’ve got a good number of options and ensure the safety of your keys or seed phrase, it’s your only chance of recovery.