You know, I used to think that snakes were solitary. But then, I kept some adult kingsnakes in a large cage one Winter. The main breeding pair stayed together all Winter and bred in Spring.
After mating, they stayed near one another off and on. He didn't mind her;she wanted a place to lay eggs, and he was an annoyance to her.
Point is, in a friggin sweaterbox, we cannot have any idea how snakes really behave socially. In a bigger enclosure, we may see a better picture, but still not the whole picture.
There is no reason that, just like taking a snapshot in time of human relations, you won't find snakes together, apart, separated, looking for mates, running off to find a nest site, returning to a mate, etc. It is not all or none, one way or another for all.
It is silly to believe that snakes breed in the wild by "happening" on one another in all cases. How can an animal that is so adept at hiding and so secretive suddenly find a mate. No, they are likely in proximity to one another. They compete for the best hide spots, food sources, etc, and the breeders that continue to reproduce stay near each other or return to one another each season until one or the other leaves for some reason or dies or is replaced by a new breeder. There is a social order to some extent. It is not a random group like electrons or something. That would be chaos for the population.
If your snakes are breeding, then they are breeding. If you don't want babies, then you will have to separate. And there is no evidence that breeding reduces lifespan. As long as the female's needs are met (adequate calories, moisture, etc) she can produce. And in nature, they produce as much and as often as food supply and conditions allow. They don't stop themselves.
