Explain to the other person what you need rather than what the problem is. Example:
“You steal money from my purse and bank account. You’re a thief”.
“I need to be able to trust you. I need everything we have to buy food, pay bills, rent, clothes for you, and if we have any extra, a treat for the family. Everyone misses out if money keeps going missing.”
If you or someone you know is struggling financially seek advice from agencies such as Child Poverty Action Group or Citizens Advice Scotland.