Physical and mental harassment given by husband and mother in law

Im kulwinder kaur nd married for 4 yrs nd hav a son of starting of marriage was not gud..still I tried to compromise with the situations in dis house. My mother in law n husband started stopping me to go my mother n father.. wen I complained dis to my parents d matter was solved between d families. Bt after this my husband and mother in law started hating my parents. Dey started complaining on small things still I ignored wat they say.. I passed my time by doing all d household work taking care of my son n everybody at home nd ignoring the comments given by my husband and mother in law. .nobody helps me in d house nd I never complained for dis also.. bt recently on an issue I hav an argument with my husband and mother in law and he started slapping me nd beaten in deep depression. The doctor gave me sleeping pills coz I cant sleep ind night. Still my husband didnt said sorry to me to forget dis incident.. im afraid if I file a case against them they wil get my son. Sometimes I thought of suicide bt my son's innocent face stops me..I cant tell my parents bcoz they wil get tensed.plz help me wat shud I do so that my son remaons with me