For example, the judge might disapprove of the dating spouse's behavior and develop a bias against them.
While such a bias is ostensibly unacceptable in the U. legal system, judges are human and biases are natural and even probable in some instances.
I certainly don't want to meet anyone younger than 40 or so. I'm Jewish but not religious, well educated, and have been attracted to Asian women since I was a teenager, my first gf Japanese American, a friend I wish had divorced her husband after his affair, a Chinese born immigrant.
Aside from my youngest son and his friends I don't know anyone in San Francisco.
As to age I'm thinking mid 40s to 65 or so, I am more in need of brains and personality than relative youth, a woman under 40 would be the same age as my oldest son.
Here we go into life's 2nd oldest hunt, the first is for food.
I am more than open to a long term relationship with or w/o minor children as long as the woman in question is not fighting regularly with her ex.
I'm 61, look like a younger Richard Dreyfus, retired and never have to work as long as I don't chase women with expensive wants.
The other spouse, if they are not dating, may develop the idea that the dating spouse was committing adultery even if that idea hadn't surfaced before.
Or, the other spouse may simply suffer anger and hurt as a result of the limited amount of time it apparently took the dating spouse to recover and move on.
Although many courts don't take children's wishes into consideration, some will, especially under the circumstance where a child is uncomfortable with a parent's new partner.
When one spouse is dating, the other spouse is likely to be resistant to shared custody agreements as well.
In addition, in some states the new relationship may be considered in the division of property or alimony determinations, so the dating spouse may not get as much as they want out of the divorce depending on the new partner's financial circumstances.