If an apology is followed by an excuse or a reason, it means they are going to commit same mistake again they just apologized for.
I'm sorry, Arty,' she whispered into his ear. 'Sorry for what?' 'For everything. For the last few months, I haven't been myself. But things are going to change. Time to stop living in the past.' Artemis felt a tear on his cheek. He wasn't sure whose tear it was.