Learn Hardcore Spanish (Latin America): Con el tiempo, mi carácter se ha vuelto más paciente gracias a la terapia y al yoga. - Over time, my character has become more patient thanks to therapy and yoga.

el carácter = temperament, general way of being (calm, impatient, kind, aggressive, etc.)
el personaje = a character in a book, movie, etc.
la personalidad = personality (more technical/psychological word, similar to English personality).

So mi carácter se ha vuelto más paciente = my temperament / the way I am has become more patient.

Why is the verb volverse used as se ha vuelto? What does the se do?

Volverse is a pronominal (reflexive-like) verb meaning to become when followed by an adjective.

Basic verb: volver = to return, to come back.
- Ha vuelto = he/she has returned.
Pronominal form: volverse = to become (change in character, attitude).
- Se ha vuelto = has become.

The se marks that the subject undergoes a change of state:

Mi carácter se ha vuelto más paciente
→ My temperament has become more patient.

Common patterns with volverse:

volverse + adjective: se ha vuelto más paciente, se volvió loco, se ha vuelto muy serio.

What’s the difference between se ha vuelto and se volvió here?

Both are correct, but they sound slightly different:

se ha vuelto (present perfect)
Focus: the change happened over a period of time and the result is still relevant now.
→ my character has become more patient (and is still that way now).
se volvió (simple past / preterite)
Focus: the change is seen more as a completed event in the past. In many Latin American varieties, this is the default past.
→ my character became more patient.

In Latin America:

Mi carácter se ha vuelto más paciente sounds a bit more like emphasizing the process and present result.
Mi carácter se volvió más paciente is also very natural and often used, especially in conversation.

Both are acceptable in everyday speech.

How is the present perfect se ha vuelto formed? Why is it vuelto and not volvido?

The present perfect in Spanish is:

[pronoun] + haber (present) + past participle

Here:

se = pronominal pronoun for volverse.
ha = 3rd person singular of haber in present: ha.
vuelto = past participle of volver.

Volver has an irregular past participle:

volver → vuelto (not volvido).

Other examples:

romper → roto
escribir → escrito
ver → visto

So:

Mi carácter se ha vuelto… = My character has become…

Why is it más paciente and not something like con más paciencia?

Both are possible, but they say slightly different things:

más paciente = more patient (adjective, describing the person’s quality/trait).
- Mi carácter se ha vuelto más paciente.
  → My character has become more patient.
con más paciencia = with more patience (noun, describing how you behave in specific situations).
- Ahora reacciono con más paciencia.
  → Now I react with more patience.

In your sentence, the focus is on a change in personality/temperament, so using the adjective más paciente is more natural.

Does paciente change for gender and number?

Yes and no:

Gender: paciente has the same form for masculine and feminine.
- Él es paciente. (He is patient.)
- Ella es paciente. (She is patient.)
Number: it changes for singular/plural:
- Singular: paciente
- Plural: pacientes

So if the subject were plural:

Mis padres se han vuelto más pacientes.
→ My parents have become more patient.

Why is it gracias a and not just gracias or por?

Gracias a is the standard way to say thanks to / because of (often positive cause):

gracias a la terapia y al yoga
→ thanks to therapy and yoga.

Structure:

gracias a + [noun / phrase]

You could technically say por la terapia y el yoga (because of therapy and yoga), but:

gracias a emphasizes gratitude / a beneficial cause.
por is more neutral and can be used for positive or negative causes.

Examples:

Gracias a tu ayuda, terminé el trabajo. (Positive)
Por tu culpa, llegué tarde. (Negative; gracias a would not work here.)

Why do we say a la terapia y al yoga? What is al?

Al is the contraction of:

a + el → al

In your sentence:

a la terapia = to the therapy / thanks to therapy
a + el yoga → al yoga = to yoga / thanks to yoga

So the pattern is:

gracias a la + feminine noun
gracias al + masculine noun (because a + el contracts to al).

Without contraction:

gracias a el yoga → sounds wrong; must be gracias al yoga.

Could we drop the articles and say gracias a terapia y yoga?

You can hear:

gracias a terapia y yoga

and it will be understood, but in natural standard Spanish it sounds more complete and idiomatic with the articles, especially with concrete, countable things like la terapia and el yoga:

gracias a la terapia y al yoga ✔ (most natural)
gracias a la terapia y al yoga que hago ✔

Dropping the articles is more common:

in headlines, lists, or very informal/telegraphic speech.
with some abstract nouns (e.g., con paciencia y dedicación).

For everyday full sentences, include the articles here.

Could the time expression Con el tiempo go at the end of the sentence?

Yes. Word order is flexible. These are all grammatically correct:

Con el tiempo, mi carácter se ha vuelto más paciente gracias a la terapia y al yoga.
Mi carácter se ha vuelto más paciente con el tiempo gracias a la terapia y al yoga.
Mi carácter, con el tiempo, se ha vuelto más paciente gracias a la terapia y al yoga. (more written/literary)

Putting Con el tiempo at the beginning:

sets the time frame first
sounds very natural and slightly more emphatic: Over time, my character has become…

Why is it mi carácter and not el carácter?

Both can exist, but they mean slightly different things:

mi carácter = my particular temperament/personality.
- Personal and specific: my way of being.
el carácter (without a possessive) often refers to:
- character in general, or
- a type of character (el carácter de los mexicanos, el carácter de mi jefe).

In your sentence, you’re talking about your own temperament, so mi carácter is the natural choice:

Con el tiempo, mi carácter se ha vuelto más paciente…
→ Over time, my temperament has become more patient…