How wrong art thou?  Let me count the ways:

(1) You quote out of context.  Cats can, and do, become repeatedly infected.
(2) As noted elsewhere (citation below), T. gondii oocysts persist and...wait for it...REMAIN INFECTIOUS for up to 4.5 YEARS.  Maybe longer.
(3) Frequency of infection INCREASES in frequency with age in free-roaming cats that continue to feed on rodents.
(4) Sure we do.  T. gondii reproduces EXCLUSIVELY in feline digestive tracts.  No kitties, no T. gondii.

http://www.academicjournals.org/article/article1380205329_Ajmal%20et%20al.pdf