Is the act of a drunkard who loses consciousness, misses a prayer, and then makes it up considered apostasy that invalidates the marriage contract, or is it like an irrevocable triple divorce?

A woman who has stopped praying due to drinking intoxicants does not become an unbeliever by that. However, she must offer sincere repentance, observe her prayers on time, fulfill the rights of her husband and children. She remains a Muslim, and her marriage remains valid.