Law changes in Alimony & Cohabitation

[Cyn05]

We currently reside in Florida. My husband has been paying alimony for the last 9 years and currently has 11 months left, in his divorce agreement they agreed that he would be responsible for alimony for ten years and that the alimony was non Modifiable. If his ex spouse were to remarry then the agreement would be terminated and he would no longer be responsible for the alimony payments. She has been living with her boyfriend throughout the entire time and has informed us via email that she will be getting married after she receives her last alimony check. She sent invitations out inviting people to come and celebrate her engagement. The ex-spouse is also on her boyfriend's health insurance plan through his job. In order for him to have added her he must have had to prove that they have been living with each other for a number of years. She also receives an inheritance each year from a trust fund which she did not state in her financial affidavit which may have affected the amount that he could have been responsible for paying.

Could it be possible for him to go back to court to try and have the alimony terminated? Would it be worth it? I know there is a new Florida statue (61.14?) that states that alimony may be terminated if you can prove that she has been cohabitating with someone and they share expenses not to mention she failed to tell the court that she receives a lump sum of money every year from a trust fund.