It's really not a good idea to house chameleons together long term unless it is a huge space with multiple basking sites and plenty of foliage so the chams don't have to see each other all the time. Any breeder who tells you that it's ok to house a male and a female together in an average-sized cage should not be trusted, in my opinion. He does not have the animals' best interests in mind.
A female xanth can continue to develop litters for a year or so from one mating. This means that most of the time she will not want to mate with the male again. She will constantly have to fend him off, leading to a very stressful life, which will affect not only her but the babies' health as well.