Eu aprendi a confiar mais na minha esposa depois daquela conversa.

Aprendi is the pretérito perfeito (simple past) of aprender. It shows that the learning happened as a completed event in the past.

So in this sentence, the speaker means they came to learn or learned to trust their wife more after that conversation.

If you used aprendia, that would suggest a repeated or ongoing past action, which does not fit as well here.

After aprender, Portuguese often uses a + infinitive to mean to learn to do something.

So:

• aprender a confiar = to learn to trust
• aprender a dirigir = to learn to drive
• aprender a cozinhar = to learn to cook

This a is required by the verb pattern here. It is not the same as the English to, even though it often matches it in translation.

Confiar means to trust. In Portuguese, it is often used with the preposition em when you trust a person, thing, or idea.

Examples:

• confiar em alguém = to trust someone
• confiar em si mesmo = to trust yourself
• confiar em uma informação = to trust a piece of information

That is why the sentence has na minha esposa: it comes from em + a.

Because confiar normally takes em:

• confiar em minha esposa

Then em + a contracts to na:

• em a minha esposa → na minha esposa

So na minha esposa means in my wife / my wife after the verb trust.

This contraction is very common in Portuguese:

• em o → no
• em a → na
• em os → nos
• em as → nas

In Brazilian Portuguese, possessives like meu/minha/seu/sua are very often used with a definite article:

• a minha esposa
• o meu irmão
• a sua casa

Because the preposition em is there, em + a minha esposa becomes na minha esposa.

In English, we do not say the my wife, so this feels unusual at first. But in Portuguese, it is completely natural.

Also, in Brazil, you may sometimes hear em minha esposa without the article, but na minha esposa is very common and natural.

Mais means more. Here it modifies the idea of trusting:

• confiar mais = to trust more

So the speaker is not saying they learned to trust their wife for the first time necessarily. They are saying they learned to trust her more than before.

This is an important nuance:

• aprendi a confiar na minha esposa = I learned to trust my wife
• aprendi a confiar mais na minha esposa = I learned to trust my wife more

In this sentence, confiar mais is the most natural placement because mais modifies the verb phrase to trust more.

So:

• aprendi a confiar mais na minha esposa

is the clearest and most natural version.

Other word orders may be possible in special contexts, but this one is the standard and most idiomatic choice for everyday speech.

It gives the time/background context: after that conversation.

• depois = after
• daquela conversa = that conversation

Together, this phrase explains when or because of what moment the speaker learned to trust their wife more.

It suggests that the conversation had an important effect.

Daquela is a contraction:

• de + aquela → daquela

It is used because the expression is depois de:

• depois de aquela conversa → depois daquela conversa

As for aquela, it usually points to something more distant in context, often something like that conversation back then or that particular conversation.

Very roughly:

• esta = this (near me / very immediate)
• essa = that (near you / already mentioned / more neutral in Brazil)
• aquela = that over there / that one back then / more distant

In real Brazilian Portuguese, essa and aquela can overlap somewhat, but daquela conversa sounds very natural when referring to a specific past conversation that stands out.

Yes, you probably could, depending on context.

• depois dessa conversa = after that conversation
• depois daquela conversa = after that conversation

The difference is in deixis and nuance, not basic meaning. Dessa often feels a bit closer in discourse, while daquela can feel more distant, more marked, or more specific as a memorable past event.

Without context, both can be grammatical. The speaker chose daquela to point to a specific conversation in a slightly more distant or emphatic way.

No, eu is not strictly necessary, because aprendi already tells us the subject is I.

So you could say:

• Aprendi a confiar mais na minha esposa depois daquela conversa.

This is very natural in Portuguese.

However, including eu can be useful for:

• emphasis
• contrast
• clarity

For example, if you want to stress I learned, not someone else, then Eu aprendi... makes sense.

Yes, that is a very good natural translation in English.

Although aprendi literally comes from learn, in sentences like this it often means something more like:

• I learned to...
• I came to...
• I realized how to...

So depending on the context, I came to trust my wife more after that conversation may sound more natural in English than a very literal translation.

Yes, it is completely natural.

It sounds like standard, clear Brazilian Portuguese and could easily be used in everyday speech or writing. The grammar, word order, and contractions are all normal:

• Eu aprendi
• a confiar
• mais
• na minha esposa
• depois daquela conversa

So this is a very good model sentence for learners.