Everyone lives by a moral code. By itself that’s not anything to brag about, as everyone does. Everyone also tends to believe they are better than they actually are, relatively speaking.
If you’re not trying to live a moral code based on objective standards set by God, you only have to live up to whatever standards you decide are right. Of course some people have higher standards than others, but in the end if there’s no reason outside of yourself to act in certain ways, however you’re living is based on what you want to do or not do, and your own internal rationalizations (sound or not).
Can she be a ‘good’ mom? Yes. Can she be a ‘good’ person? As far as society is concerned, yes. Can she be a ‘good’ person in God’s eyes? On her own, no. She can be a moral person (all people are, their codes vary), she may even have high moral and ethical standards, but that will not save her. None of our good deeds save us.
God will judge her however in perfect fairness and justice, as He will everyone.
If you are trying to live a moral code based on objective standards set by God, you only have to live up to whatever you decide those standards are.