I think Kirzon loved the woman and Jadzia, still being a Dax, had feelings for her.
Torias Dax (male host) used to be married to Nilani Kahn (female host).
Now the Dax and Kahn symbionts both have female hosts, but they remember the heterosexual relationship. The other Trill characters in the show think Jadzia Dax and Lenara Kahn having a relationship is taboo, but it has nothing to do with the current hosts both being female.