3、Im filled with deep regret and heartfelt sorrow for the pain and disappointment I have caused you; please accept my sincere apologies.
4、Iould like to express my utmost remorse and sincere apologies for my thoughtless actions that hurt and let you down; I hope you can find it in your heart to forgive me.
5、Im genuinely sorry for my careless words that caused you distress and I truly regret any harm they may have caused; please accept my heartfelt apologies.