Lent money you never mention turns into resentment you never mention either.

Money that is owed and unmentioned does not sit still. It turns into a small running calculation you both carry, and because neither of you wants to raise it, it gets paid in another currency: a little distance, a joke with an edge, a declined invitation. The silence does the damage rather than the amount.

If you are owed something, ask once, kindly, with a specific sum and no story attached. If asking feels impossible, decide to let it go properly and stop keeping the tally. Next time, lend only what you could write off without it changing how you feel.