please help im in a mess

I am a 25 year old Indian woman living in the U.K. with my British husband
of 4 years and our 17 month old son. I have permanent leave to remain in the
U.K. and can apply for British citizenship as spouse of a British citizen. Unfortunately our marriage is breaking down and we might seperate so can I apply for British citizenship on some other grounds? I want to apply asap. to protect my rights incase this happened.

Please could you advise about my son as I have no family here or anyone I can trust. I have been a house wife since I came here, I have no money. Also can my British Citizenship be revoked if we divorced or seperated? I do not want to be deported as I fear I will lose my son as he was born here and is a British citizen.

Could I keep my Indian passport and can I use it to travel to India if I become a British Citizen? What can I do if I cant? Should I even apply for a British Citizenship in the first place?

Also what is the maximum time I can stay in India without losing my permanent leave to remain status over here.

Thank You.
E.