She can't be Luffy's mother.
In 2009 interview, Oda said Luffy's mother is still alive.
Considering Shakky ~ Ray and Boa ~ Luffy, we can deduce that Tritoma fell in love with a pirate.
At the time of God Valley, Shakky was the empress and she quit around that time.
So, Tritoma became Empress around that time and died 13 years before the current story.
Only two pirates fits - Shanks and Mihawk.
Age gap would be big but it's possible Tritoma became Empress at an early age or oda doesn't care about the age gap