Gambling is paid entertainment, never a source of income. If it stops being entertainment, the tools below exist and they work.
Self-exclusion
Latvia keeps a national self-exclusion register. Entering it closes access to every licensed operator at once — far more effective than excluding yourself site by site.
Deposit limits
Set them in a calm moment, not after a loss. Most operators delay any increase with a cooling-off period of 24 to 72 hours — that delay is precisely what makes limits work.
The signs
Not the amount, but the loss of control: playing longer than intended, returning to recover losses, hiding the extent of play, borrowing to continue. Several together is reason to speak to a professional.