Anymore, yet, lately
 

I haven't gone there yet (yet indicates something unaccomplished. It is always accompanied by the negative)
I haven't gone there lately/I haven't gone there lately (lately something accomplished or being accomplished. It can be positive or negative)
I don't go there anymore (Anymore is the opposite of yet.)It is a negative word. It is correct to use the double negative when anymore is used. Anymore and yet may be the only cases in English where the double negative is gramatically correct.

Examples: Lately I'm tired/not tired. This means that currently I am habitually tired /not tired(these days can be used in place of lately)

I'm not tired anymore This means that I am no longer habitually tired
I'm not tired yet. This means cansancia no me llegó todavía.

Yet and anymore are negative words that use the double negative(anymore requires the double negative. There's an option not to use the double negative with yet. Let me know if your interested)

Lately/these days/nowadays can be both negative and positive.

Do you find this complicated? I do.

Eres un cielo, Poli. Great explanation. Hasta Alfonso lo entenderá...

I'm quite impressed, Poli. Thanks a lot!

You say el cansancio: No me llegó el cansancio (aún / todavía). No estoy cansado aún / todavía.

Yeah, how do you use yet in an affirmative sentence?

Children often use a sentence hated by most parents . During a long trip, five minutes after leaving home and intermittently and frequently till you reach your destination a gazillion hours later:
Are we there yet? = ¿ Ya hemos llegado?
Are we there yet?
ditto
ditto
...
Are we there yet?

Another way of saying I haven't gone there yet is I have yet to go there.
I have yet to go there is more proper, less used and probably more British.

Gemma you are right about Are we there yet?, but that's only in the form of a question. The answer if negative would be, No we are not there yet.
You would never say, Yes we are there yet, because yet is a negative word that takes the double negative.