Hiya
do you have any other fish in your tank apart from the paradise? How big is your tank?
Males are known to be very agressive, so you need to make sure you have plenty of plants (loads of em) and also lots of hidey places for the female so she can escape from the male or she will get very stressed and her condition will worsen. She could be using the filter as a hidey place but she could also be that stressed that her breathing is becoming affected.
Also has the female spawned recently (you may notice bubble nests) Sometimes after spawning a male will be very very agressive to the female as he no longer has any use for her.