Let me quote you the Hindu scripture called Narad Smriti,That fiction was based on reality. Is remarrying even young widows part of Hindutva ? The Indian situation says otherwise.
Alternative to what ?
97. When her husband is lost or dead, when he has become a religious ascetic, when he is impotent, and when he has been expelled from caste: these are the five cases of legal necessity, in which a woman may be justified in taking another husband.