1)you can file for divorce on grounds of mental cruelty .
2) you can also seek custody of your son
3) since your child is only 3 years old court may award you custody of the child
4)in the alternative court may award you joint custody of the child wherein child stays with you for 183 days and with father for 182 days .
5) you can also seek maintenance for the child
6) contested divorce cases take around 5 years to be disposed of
7) mutual consent divorce would take around 6 months
8) if your husband is willing both can settle down in USA away from constant interfernce of your in laws