I find this story very hard to believe. If the two had attorneys, the husband's attorney would have objected to this testimony and the judge would have sustained the objection. If they were pro-se the judge would not have allowed this testimony to come in.
Divorces are about one and at most two things. How is the property divided up and who gets the kids. The having sex with horses would not be pertinent to either of those issues unless he was having sex with horses IN FRONT OF THE KIDS. How to divide the marital property has zero to do with sex of any kind. Now if he was spending money on oats or hay to sweet talk the stud into mounting him that might be deemed as a fraud on the community and an offset would be allowed. But she would have to PROVE how much was spent. I guess maybe the cost of the costume could be offset and maybe the cost of the MASSIVE amounts of lube he purchased. But then again, if the horse whisperer was my client there would have been no trial.