While one incident took place in Rohtas district's Khaira village, the other was in Aurangabad's Judahi village.
Savita Kumari from Khaira called off the wedding when she found her groom sloshed to the gills, minutes before the ceremony Sunday night.
Dressed in traditional red finery, the plucky woman, in her 20s, was informed by her friends that the groom was drunk and refused to marry him.
"I decided not to marry a man who is drunk ahead of wedding. That was an indicator that he was not a responsible man and unfit for me," she said.
She found full backing from her relatives, family sources said.
"She refused to marry the man who was drunk. I did not force her to marry against her wishes," her father Devender Ram said.
He approached the police but was advised not to do anything about it. "Police have no role if a woman refuses to marry a drunk groom," a local police official said.
In the second case the same night, Lalan Singh took an equally courageous stand when he took the call not to get his daughter married to a drunk and asked the 'baraat' to return.
"The drunk groom was exposed when he came to our house. He was so drunk that he assaulted some people and threw chairs at women during the pre-wedding rituals," Lalan Singh was quoted as saying.
The groom's father Balram Singh said his son's friends had mixed alcohol in his cold drinks, but Lalan Singh would have none of it.
"I was adamant not to marry my daughter to a man who was drunk on his wedding night," Lalan Singh said, recalling how he asked them to go back.
The families of two brides represent a welcome trend in Bihar, where such stories were virtually unheard of till a few years ago.
The pattern in large swathes of the state, particularly in the villages, was and still is, the bride being spurned for reasons such as insufficient dowry.