let bygones be bygones(to disregard or ignore a past difficulty in a relationship or an offence) verb [UK: let ˈbaɪ.ɡɒnz bi ˈbaɪ.ɡɒnz] [US: ˈlet ˈbaɪ.ˌɡɒnz bi ˈbaɪ.ˌɡɒnz]
hacer borrón y cuenta nuevaverb
wipe the slate clean(to make a fresh start, forgetting differences) verb [UK: waɪp ðə sleɪt kliːn] [US: ˈwaɪp ðə sˈleɪt ˈkliːn]