Apology

[Drdrtoledo]

If a father is apologizing to his daughter for a dereliction of his duty to protect her, is "mea culpa" sufficient?
I am trying to say "I'm sorry I failed you" or "I'm sorry I let you down" or "please forgive my failure (of my duty to protect you)". Mea culpa doesn't feel right/sufficient. It just reminds me of the modern day "My bad". Couldn't find anything in forum search. TIA

 

[Pacifica]

You could say me paenitet tibi defuisse ("I'm sorry that I failed you", "I regret failing you") or ignosce, quaeso, quod tibi defui ("please forgive me for failing you").