Well, there are variations in the Spanish spoken in different Spanish-speaking countries (The same way that there are differences in English, for example with the words
center or different meanings for
So of course we have 1st, 2nd and 3rd person, singular and plural. Basically: yo, tú, el/ella, nosotros, vosotros, ellos. Oh, well, there is another one, which may make things a little bit confusing,
usted/ustedes, which is the formal way of addressing someone (a 2nd person). The only tricky thing about it is that for verb conjugations it will use the 3rd form instead of 2nd, even if it is a 2nd person form.
But, why that woman had never heard of
tú? Well, among some of these variations of Spanish they don't use
vosotros. See this reference for a basic look into this.
Some of the countries use voseo so instead of saying "eres muy amable" would say "Sos muy amable", using "vos" instead of
tú ("Vos sos muy amable").
Some other countries would even use
sois, like "sois muy amable", with
sois being a 2nd person singular form even when for another Spanish would be plural.
Vosotros sois muy amables.
Some countries favor the use of the
ustedes form for 2nd person. For example, a teacher in Spain would ask her students
Niños, qué veis aquí?
But a teacher in Mexico would say
Niños, qué ven aquí?
Again, the usted form uses a 3rd person conjugation.
So, this is not to give you a complete insight about all the differences and/or all the variations, but just to tell you that these variations exist, and thus some countries don't use
tú because the favor
vos (and maybe use a particular conjugation for it).