If the circumstances were such that your mom truly needed the money to pay bills for electricity, gas, or telephone ( genuine necessities) I can understand how desperate she must have felt when she borrowed the money from you. I think that her paying you back, and with interest, is to her credit. I would ask you to compromise a bit, and understand that parents are only people...people who make mistakes, people who are sometimes desperate, and so on.

What stand out to me as abusive is that your mom frightened you the way she did. That is not okay.

Forgiveness, however, is something you might consider for your own peace of mind. The incident was thirty years ago. Life is too short to spend any more of your time stewing over this. As for ever borrowing money from your children, well, no one wants to do that. I sure don't - but I have. And I'd say that part of being "family" is being flexible enough to place relationship over money. Yes, money sometimes represents other things (like pride about accomplishment), but when all is said and done, money is money. It comes and it goes.

I'm curious...what is your relationship with your mom like now?