I feel like everyone's ignoring one potential avenue of thought this could go down.
What if Tritoma had love sickness for Shakky?
I don't think anyone's ever said you could only get love sickness for someone of the opposite gender.
Tritoma did seem to be one of the Kuja who were in charge of everyone's fan mail. Who's to say if she couldn't slip a few of her own letters in with everyone else's? And when Shakky eventually left the island to be with Rayleigh, Tritoma's feelings could have gone unrequited, or even unsaid in the first place. No one else may have ever known how she felt.
Or hey, maybe it could be someone else. Let's say Miss Buckin. Maybe Tritoma found out that Miss Buckin was trying to clone herself and just the thought of two Stussys running around was just too much for her poor heart to take. Or even Big Mom. You know what one race that Big Mom might not have had in her family yet? The Amazons!
Or, and I'll admit this is very unlikely, is it a coincidence that her name is TRI-toma? Is it possible for someone to get love sickness for more than one person at a time? Maybe she had love sickness for two different people at the same time? This is a children's manga, so I doubt it. But, ALL avenues deserve to be considered here! For science!
I don't know. I feel like other options are on the table. Maybe it's not likely. It's makes for a interesting enough story, but it doesn't really move the story forward in any way, like her being in love with someone else would. But, I'm not sure if Oda cares or not? It's sometimes hard to predict what his priorities are. But, I could see Oda doing something like this.