We are apprehensive that cousin's wife might file false case

My brother in law's wife went for Rakhi to her mother's home and now she is asking for separation to join back. She want to live separately and doesn't want to support parents. We are afraid that she might plan to put some false case against the family. Need help to understand how can we get ourself proactively safe from such case. Also in case we need separation, what is the procedure as the marriage is just 6 month old and what shall be financial impact on boy's family. It is very disturbing and their family is asking a boy to come to their hometown to settle down the case...!!! They are money oriented and want to get regular part from boy's income which is refused by boy being low salaried. Also how shall it get impacted on parental property, does girl has some legal share on teh same !!!