Responses
I've always thought the most logical explaination for Sanji's values about women is that his mother sacrificed her life dor him. So, yes, I think what you say is very probable. But, at the same time, Oda doen't like to repeat stories, and we already have Bellmere, Olivia and Otohime (specially Bellmere). So, I'm not sure if Sanji has "a mother" background sob story. Maybe it's not a mother, or maybe it's not just one woman. Anything can happen, Oda always surprises me.
also I like to think that maybe, it was Sanji mom who send him on the ship, maybe to escape something, then his mother got killed for her action and thats why Sanji want to protect every woman in sight....because they all remind him of when he was a kid and unable to protect his own mother ??
just another theory...we will know later I guess