Hindu widows like widows elsewhere are allowed to live their lives as they choose to in India now.
Sati, the practice of burning oneself with ones husband was a practice from the past, which is now illegal and punishable. it originated at a time when hindu women in the northwestern regions of india, threw themselves into the funeral pyre of their husbands, to avoid being raped and enslaved by the invaders, during the 3000 years of muslim invasion of india.
there are no specific temples where widowed women live. Manusmriti lays down some rules for widowed women, you could probably google it out. however, if manusmriti was practiced as law, is debatable. Manu was one of the kings, and smriti means thoughts.
hope these help you with your own truth seeking.