What does this sentence mean?

[onetwothree]

"I haven't talked to you in forever".

Could you please tell me what the sentence above means? Thank you.

[RonBee]

It means a long time.

[David L.]

Where did you find this?

It is the same as saying, "I haven't talked to you in ages." - it is so long since we have talked, it feels like an eternity, forever.

However, I haven't seen this version before. Is this teenager-supercool talk?
Sounds like something out of Grease! Haven't seen you in, like, forever, man. = becomes Haven't seen you in forever.

[bhaisahab]

"I haven't talked to you in forever".

Could you please tell me what the sentence above means? Thank you.

I have heard teenagers using "I havn't talked to you since forever."
As for the meaning, as Ronbee says, it means "in/for a long time."