Divorce - handicapped

My friend is disabled by one leg and his wife has ran away with another person and they both had a baby of 3 years old.Her wife has left the 3 year baby too.she has confirmed she will never again come back but she is asking for the baby.But my friend dont want to leave her baby.And when we are proposing for divorce she is not even ready for that.How can we sort this out

Sir, if your friends want to live with her wife then please ask him to file restitution of conjugal rights U/S 9 of Hindu Marriage Act, 

And if your friends do not wish to live with her then he can file Divorce petition on the ground of cruelty and Adultery U/S 13(ia) , along with that he can also claim maintenance U/S 24 of H.M.A  from her wife as she is physically capable of working, 
In H.M.A also he can ask for the custody of the child(only if he wants)