Είχα να δω την πεθερά μου από τον Ιανουάριο, γιατί έμενε στο χωριό.

Here it does not mean obligation.

In this sentence, είχα να δω is the past version of a very common Greek pattern:

έχω / είχα να + verb

This can mean I haven’t / hadn’t done X for some time or it has / had been since I did X.

So:

Είχα να δω την πεθερά μου από τον Ιανουάριο
= I hadn’t seen my mother-in-law since January
or more literally
= It had been since January that I had seen my mother-in-law

Greek learners often confuse this with obligation, because έχω να + verb can sometimes also mean I have to do something in other contexts. But here, because of από τον Ιανουάριο, the time meaning is clearly intended.

They are related, but not identical.

δεν είχα δει simply means I had not seen.

είχα να δω adds the idea of elapsed time:

• δεν είχα δει την πεθερά μου = I had not seen my mother-in-law
• είχα να δω την πεθερά μου από τον Ιανουάριο = I hadn’t seen my mother-in-law since January

So είχα να δω is the more natural choice when Greek wants to emphasize how long it had been since the last time.

After να, Greek uses a special dependent verb form. In learner-friendly terms, you can think of να δω as to see / see in a dependent structure.

Here δω is used because the speaker is thinking of seeing her as a single complete event, not as an ongoing process.

So:

• να δω = to see / see her once, as a whole event
• not να βλέπω, which would sound more ongoing or repeated

That fits the meaning I hadn’t seen her since January: it refers to the event of seeing her.

Yes. δω belongs to the verb βλέπω.

This verb is irregular across its stems:

• present: βλέπω = I see
• aorist: είδα = I saw
• dependent perfective form: να δω, θα δω = that I see / I will see

So even though βλέπω and δω look very different, they are forms of the same verb.

This is one of the verb families Greek learners simply need to get used to.

Because την πεθερά μου is the direct object of δω.

The basic dictionary form is:

• η πεθερά = the mother-in-law

But after the verb see, Greek needs the accusative case:

• βλέπω την πεθερά μου = I see my mother-in-law

So here:

• η πεθερά = subject form
• την πεθερά = object form

πεθερά means mother-in-law.

In this sentence, την πεθερά μου means my mother-in-law.

It does not mean stepmother.
A stepmother is μητριά.

In Greek, possessive clitics like μου usually come after the noun:

• η μητέρα μου = my mother
• ο φίλος μου = my friend
• την πεθερά μου = my mother-in-law

So this is the normal Greek order.

If you want extra emphasis, Greek can use a fuller structure such as:

• τη δική μου πεθερά = my own mother-in-law / my mother-in-law in particular

But in ordinary speech, την πεθερά μου is the standard pattern.

Greek very often uses the definite article with names of months:

• ο Ιανουάριος = January
• τον Ιανουάριο = January, in the accusative

After από, the month appears in the accusative:

• από τον Ιανουάριο = since January / from January

So the article is completely normal here.

Here it means since.

Greek uses από both for place and time:

• από την Αθήνα = from Athens
• από τον Ιανουάριο = since January

So the exact English translation depends on context. In this sentence, because it refers to time passing up to a later point, since is the natural translation.

Here γιατί means because.

Yes, γιατί can also mean why in questions:

• Γιατί έφυγες; = Why did you leave?

But in this sentence it introduces an explanation:

..., γιατί έμενε στο χωριό.
= ..., because she was living in the village.

So context tells you which meaning is intended.

έμενε is the imperfect of μένω.

The imperfect is used here because the sentence describes an ongoing background situation:

• έμενε στο χωριό = she was living in the village / she lived in the village

This explains why the speaker had not seen her.

Greek uses the imperfect for things that were:

• ongoing
• habitual
• background information

So έμενε fits well.

Because έμεινε is aorist, and that would suggest a more bounded, completed event, such as:

• she stayed
• she moved in
• she remained

But έμενε describes an ongoing state:

• she was living
• she used to live

In this sentence, the speaker is not focusing on a single completed act of staying somewhere. The point is that her living in the village was the continuing situation that kept them apart.

στο is the contracted form of:

• σε + το = στο

So:

• στο χωριό = in the village / to the village, depending on context

Here, with έμενε, it means in the village:

έμενε στο χωριό = she was living in the village

Also, χωριό is a neuter noun:

• το χωριό = the village

Because Greek often leaves subject pronouns out when they are not needed.

The verb ending already shows the person:

• έμενε = he/she/it was living

So Greek does not need to say αυτή unless the speaker wants emphasis or contrast.

This is very common in Greek:

• πήγα = I went
• ήρθες = you came
• έμενε = he/she was living

Yes. Greek word order is more flexible than English.

This sentence could be rearranged, for example:

• Είχα να δω από τον Ιανουάριο την πεθερά μου, γιατί έμενε στο χωριό.
• Γιατί έμενε στο χωριό, είχα να δω την πεθερά μου από τον Ιανουάριο.

But the original order is very natural.

Greek changes word order mainly for:

• emphasis
• rhythm
• information structure

So the original sentence is not the only possible order, just a normal one.