Why did Bholi accept to marry Bishamber? Why did she refuse to do so later?

Bholi was a confident and educated woman when she was to marry Bishamber. Although she had no interest to marry, she agreed to save her father’s honour. When Bishamber saw the marks on her face during the ceremony, he suddenly demanded a high dowry. He didn’t listen to the plea of reducing it. When he was going to put the garland, Bholi publicly said no, calling him a selfish old man. She was enraged by Bishmaber’s behaviour and declared that she would her parents and teach in the school for the rest of her life.