75:13 If a blind woman is married, her husband lights the candles and recites the bracha (assuming that he can see – Mishnah Brurah 263:14). If she does not have a husband and lives alone, she lights the candles and recites the bracha herself. If she lives with others who also light Shabbos candles, the blind woman should light without reciting the bracha. If she is the head of the household, she lights first and says the bracha, then the others light and say the bracha.
75:14 If a woman forgot to light Shabbos candles, for the rest of her life she lights an additional candle beyond what she lit before. If this happens several times, she lights an additional candle for each instance. (A poor woman may simply use a little more oil or a longer candle – MB 263:7.) This penalty was imposed to make her more careful; if she was prevented from lighting by circumstances beyond her control, she does not need to add an additional candle.