Use of Past Perfect for a state/action that isn't true anymore

Question

The traditional definition for the past perfect tense is thT it's used to convey that something occured before another action in the past. Here are some example sentences from a website:

I had never seen such a beautiful beach before I went to Kauai.
(me having never seen such a beautiful beach comes before me going to Kauai)

I did not have any money because I had lost my wallet.
(Me having lost my wallet comes before me not having any money)

Tony knew Istanbul so well because he had visited the city several times.
(Him visiting Istanbul comes before him knowing Istanbul so well)

When I look at the other websites, I see similar examples. My question is that can we use the past perfect to describe an active that isn't true anymore. As in:

John hadn't seen Joe for quite some time.

In the sentence, it isn't clearly stated if an action happens after John having not seen Joe; but assuming John hadn't seen Joe for some time before he saw him in a party yesterday, is the sentence above acceptable?

We have other alternatives for the past perfect, but I think they might not mean the same thing, or might not be correct. For example, if I said:

John didn't see Joe for quite some time.

or

John hadn't been seeing Joe for quite some time

I think the first sentence would suggest John still haven't seen him, and for the second sentence, I'm not sure if we should use "see" in the progressive. Since it's a state verb, it's mostly used in the simple tense, e.g.

I see a man outside.

And not,

I'm seeing a man outside.

So should I use the past perfect continuous or past perfect or what?

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Edit: Per Katy's comment, it's okay to use the past perfect continuous with "see". But what if it's another word? Consider "to lose". If I said:

I lost my keys.

I think it would be understood I still hadn't found them. Can I say:

I had lost my keys.

to mean that I'd lost them but later I found them. And can I do this with, say, "to dye" too?

She had had her hair dyed red. (She had had her hair dyed red, but later she had it undyed.)

Answer 1

You need to put a verb into the past perfect tense to indicate a contrast between the time of that verb and some other, later time, which you are referring to in the simple past tense. In your first three examples, the verb in the simple past tense occurs in the same sentence: went to Kauai, did not have any money, knew Istanbul. For the past perfect to make sense in your other examples, there needs to be something described in the simple past tense in the surrounding context, which provides the contrasting time. Usually this comes from the fact that you are telling a story in the past tense. The type of verb doesn't really matter.

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The Sunday night game club

To illustrate, here are a few little stories with a couple of your example sentences, to illustrate the kind of context where each tense makes sense.

In February, Joe stopped attending the Sunday night game club. John didn't see Joe for quite some time. Lacking an opponent for Parcheesi, John eventually stopped showing up, too.

Joe knocked on John's door, hoping for a game of Parcheesi. John hadn't seen Joe for quite some time. John happily invited him in.

In the first story, each sentence describes activity (or inactivity) at a time later than the previous sentence. So, all that's needed is the simple past tense.

In the second story, the second sentence "backs up" for a moment. The past perfect is needed to indicate that the sentences do not follow chronological order. Writing it like this:

Joe knocked on John's door, hoping for a game of Parcheesi. John didn't see Joe for quite some time. John happily invited him in.

would suggest that after Joe knocked on John's door, John couldn't see Joe—as if Joe were invisible or ran away after knocking on the door.

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A digression to India

This next story illustrates how the aspect of the verb (continuous or not) doesn't matter:

In September, I saw John and Joe playing Parcheesi. Joe hadn't been attending the game club in quite some time. It turned out that Joe had been traveling in India all summer. When the game was over, Joe told us all about the great Parcheesi masters of Jammu and Kashmir.

The simple past tense describes the main timeline of the story: the events one night in September at the game club. The middle two sentences "jump out" of that timeline to a previous time, so at least the first one needs to be in the past perfect. The second one could have been worded was traveling in India, since once the contrasting earlier timeline is started, it's usually not necessary to repeat the past perfect to continue it.

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Lost keys

If you walk up to the hotel desk and say:

I lost my keys.

yes, this suggests that you have not found them yet. But if you say:

I had lost my keys.

this suggests that you have more to say, and you will say it in the past tense. The past perfect "points to" some later past time in its context, expressed in the simple past tense. Without that contrasting time, the past perfect sounds strange, like a mistake.

Note that you don't need the past perfect to say that you found your keys later:

I lost my keys this morning, but I found them again this afternoon.

The past perfect is not appropriate here (though it's not wrong), because the timeline is chronological.

By the way, to clearly indicate that you lost your keys and this is still a problem right now, you say:

I have lost my keys.