Asking for money owed

[porridgewithalmondmilk]

Not really an AIBU but how do you go about getting money off people who manage to get a considerable sum from you quite stealthily, by saying "oh, if you get/book/buy mine, and I'll give you the cash later?"

But "later" never comes

I've now realised this person has form for this but I'm still considerably out of pocket and I want to claim mine back - any ideas for how I can politely but firmly demand it back? :)

I suspect that is how she sees me to be honest - unfortunately when it's somebody you don't see a lot of, opportunities to ask for the money to be repaid are few and far between (and also mean the occasions are special ones like weddings where you don't want to make a scene or create bad feeling.)

I know I need to be more assertive but it is difficult. I feel pretty miserable about it to be honest.

I had a friend like this, would always get me to put her share of the bill on my card and never pay it back.

I ended up always taking just enough cash to pay for mine.

I know I need to be more assertive but it is difficult. I feel pretty miserable about it to be honest

Well, be cross, too.

You can't just command yourself to feel certain emotions, Eldritch :)