Marriage is canceled before marriage

I have canceled the marriage due to the bad behaviour of the girl and I felt she is not compatible for me and my family. Due to frustration I have scolded the girl over phone and they have recorded and showing to everyone and In turn the girls family have called my parents over phone and they have also scolded my parents which we have recorded. And Girls family is asking the money back which they have paid as advance to the marriage hall, photographer, flowers etc. should we give the money back to them ? We have not done any kind of engagement. We had purchased engagement rings and we have given all their assets back to them and they have given our assets back. Now after receiving everything back they are asking for money which they have made as part of advance. And they are threatening to sign a bond saying we or our relatives or friends won’t spread any bad news about them if any one spread they will take legal action on us. Is this acceptable and Should we need sign the bond?