Wa alaikum Assalam, Dear Sister!
The situation is indeed tough but the action is clear. A Muslim woman cannot remain wedded to a Hindu.
JUST AN HUMBLE OPINION: Others might have better thoughts.
Seek the support of your family and friends and hire a lawyer in personal law. Where do you live?
According to laws in India and Pakistan, no woman can be made to live as a wife by force. Your husband cannot take your little kids away from you. They will decide their own future when they grow up.
At this time the only option for you is to seek immediate divorce through the court of law. Please consult your family and a lawyer.
For the future, put your trust in Allah.
A lifelong student