No, cheetahs do not mate for life. Quite the opposite. To be clear, ‘mating for life’ means that a male and female form a lifelong partnership. The behaviour of the cheetah is at the opposite end of the spectrum. There is no such partnership.
The female comes into heat (oestrus) about every 12 days. When cheetahs were observed in a captive group the males fought one another to stay close to the female. One male dominated the others. The males increased their urine spraying.
In the wild, male cheetahs move towards unaccompanied females and can approach mothers with cubs. When a male gets close he sniffs the vegetation where the female has been lying and he may try to sniff the female’s vulva.
Where there is a male coalition of two or three they sometimes threaten each other during an encounter with a female under these circumstances. One report observed that “a coalition of males struggled for the chance to mount the female by pushing each other off with their heads”.
In another report a captive male at a safari park in the Netherlands “seized the female by the scruff of the neck and held her so that she could not move away. The copulation lasted for about one minute.”
The cheetah behaves like the domestic cat in terms of mating and partnerships. There is no such thing as a mate for life. A colleague of mine, Elisa, wrote an article many years ago describing the mating between male and female domestic cats as an act of rape. That description caught the eye but it is not strictly correct because the female arguably consents to it. But it does look like an unruly orgy.
In terms of cheetah social organisation, females are solitary or accompanied by dependent young. Males are either solitary or live in stable coalitions of two or three. Some male coalitions consist of brothers but sometimes they are unrelated. Male cheetah coalitions “mate with as many females as possible”. That sums up their behavior as the antithesis of a ‘mate for life’.
I have relied upon, as usual, the book: Wild Cats of the World, the best book on wild cats. I have taken the liberty of quoting the book on occasions for accuracy. The authors of the book, Fiona and Mel Sunquist, use a copious number of references. These are often scientific studies. If you would like details of these references please ask me in a comment and I’d be happy to provide them.